It was the most Hobbesian thing Twilight had seen since graduate school.

A path of trampled snow marked the line ponies must have been standing in before order broke down. The doors were open but impassible due to the sheer mass of overweight bodies, writhing and groaning like in paintings of Hell that Twilight had seen in the Canterlot art museum. Others had taken to throwing things at the windows: Small rocks and pieces of wood bounced off harmlessly. Shouts of protest filled the air. Things were on fire.

“You swore you’d never leave us!” a filly sobbed amid the chaos. “You were supposed to take us all to Cakeland with you!”

Twilight resolved to talk to Pinkie Pie about her advertising strategy later. Right now she needed to find out why Sugarcube Corner was going out of business. Closing her eyes, she activated her horn and teleported inside the clear glass doors.

And into the calm.

The heat shocked her, setting her gasping and sweating profusely. She was surrounded by ponies—sweating, fat ponies, milling around stands of cakes, talking excitedly—

No violence.

Twilight straightened up. Through a gap in the crowd she could see the madness just outside the clear glass windows. But inside, ponies shopped.

Twilight struggled to push her way to the front. She needed to find Pinkie Pie. And she needed to get away from the sort of pony who ate at Sugarcube Corner.

“—what I like about the piCake is that it has such a great eater interface—”

“—no worms—”

“—I love being able to customize my own—”

“—and it’s only slightly more expensive—”

Twilight shut her ears to the insanity. The whole place was a madhouse, a private galaxy warped by the sheer mass of Pinkie’s craziness. Pinkie was the star of the local cake scene, and like planets trapped in their doomed orbits, ponies swirled around Pinkie like moths to the light. And eventually enough cake had pretty much the same effect on ponies as fire did on moths.

She pushed her way past an obstinate and severely overweight stallion lamenting that he had just updated to the Premium Dessert Plan Star Plus Extra, which meant that he could get icing anywhere, and stopped to lean against a long counter crowded with ponies and cakes.

“How can I help you today, miss?” said a bright young pony behind the counter.

“Just catching my breath,” Twilight panted. Her head felt light. She couldn’t get a proper breath in. “What—“ cough— “what do you do here, anyway?”

“I help customers, of course!”

“Aren’t you going out of business? Like, right now?”

“That’s right, miss!”

Twilight looked at her. “What do you help ponies with?”

“With cake and cake accessories! This is the Party Bar. Cakes, batters, icing, spoons, whisks, bowls, pans, spatulas, eggs, egg beaters, egg-beating technique—”

“No!”

The fat stallion from before lumbered up to the bar, not exactly pushing so much as rolling Twilight away.

“Hey, uh, I really like Sugarcube Corner cakes and stuff,” he said, sweating profusely.

“Wonderful, sir. How can I help you?”

“Well, I got into cakes the usual way. Baking birthday cakes, that sort of thing. I knew some of my friends were into Sugarcube Corner, but I didn’t know much about it. Well, one day I tried the, uh, I think it was a peanut butter brittle cupcake, and wow, it was just amazing.”

“Oh, great!”

“So I started branching out, made some apple cakes, gave a Marechusetts cream pie a shot, and, you know, I got the cake bug in me. Bought all the Sugarcube Corner equipment and books, and of course I come here every day for at least one square meal of cake. So now I’m working on a better than clop cake—”

“Very good, sir!”

Twilight still hadn’t caught her breath, but the knowledge that the opportunity cost of waiting was listening to more of this drivel sent adrenaline flooding through her. She had fought past pony-snatching vines; she could get through a crowd of cake-filled, terribly sweaty ponies.

She was almost to a counter lined with cakes with a cash register in the center when she heard a pony say, “Well, muffins simply don’t have the same eater interface, you know, it’s all about the eater interface—”

And inside Twilight Sparkle, something snapped.

“What,” she said loudly, “is an eater interface?”

The pony turned to look at her, surprised.

“You know, the way your hoofs and mouth interact with the cake.”

Twilight stared at her.

“It’s very important,” the pony said. “Only Sugarcube Corner does it right. Have you never eaten a cupcake before?” She snickered, elbowing her friend.

“Cake is okay every once in a while, but most of the time I’d rather have a muffin or something, honestly,” Twilight said.

The silence blasted through the room like the rage of an Alicorn.

“HEY, EVERYPONY! YOU BETTER BE READY TO PARRRRTAY!”

The ceiling exploded into pink. Balloons fell like bombs in a machine-gun rain of confetti and streamers. In the center of it all was the pinkest pony, standing on the counter.

“PINKIE!” the assembled ponies cheered.

Pinkie Pie spread her hoofs over the mass of frenzied fanatics.

“I’m so glad to see you all at my final clearance sale ever! Who’s ready for some cake?!”

The crowd’s response was incoherent. Some ponies were screaming, others openly weeping.

“It’s really her!” said a weeping filly. “She really is real!”

“We can’t eat cake on a cold stomach!” Pinkie said. “We have to work up an appetite! Let’s all do the Physical Perks!”

Twilight struggled lamely to keep her last hold on reality from sliding away entirely. Pinkie was leading the entire store in calisthenics.

“And one two three four one two three four!” Pinkie leaned up from one leg, bringing her front hoofs around in a tall arc and down until they were touching the other hind hoof. The worshipful ponies below followed in creepy unison. “And one two three four two three four one….”

Pinkie Pie blew on a whistle to signal the end of the Physical Perks.

“Who’s hungry?”

The crowd roared.

“But first we have to do one thing! One last time!”

Pinkie Pie pointed to a monitor that lowered down onto the west wall. The still image of a tired, harassed-looking stallion whom Twilight didn’t recognize flickered onto the screen.

“Oh no, it’s Mr. Landbiscuit! He wants to compete for Sugarcube Corner’s market share!”

Ponies hissed. Others screamed. After just ten seconds of his image on the screen, expressions of rage erupted from the ponies. They hopped up and down, howling their fury and fright.

“Swine!” a pony screamed. “Swine! Swine!”

Twilight was suddenly glad Fluttershy wasn’t there. On second thought, Twilight fervently wished Fluttershy was there. She could have used a bodyguard.

The ponies didn’t rest. The noise intensified, built to a crescendo, and as Twilight stuffed her hoofs over her ears and tried to hide, a spoon bounced off of the monitor. The ponies threw spatulas, pans, forks, anything they could get their hoofs on, but not cake, never cake.

They stopped.

Pinkie Pie had spoken.

“That was fun,” she said. She sighed a little. "I'm going to miss that."

The monitor withdrew, and, shakily, so did Twilight’s hoofs from her ears. She looked up at Pinkie Pie.

She was standing on two legs.

In her hoof she held a streamer.

“Let’s eat cake,” Pinkie Pie said.

Ponies crowded around the counter, but they didn’t push. They seemed to know exactly where to go and how to make maximum use of the space as if they had done this a thousand times in exactly the same way before.

“I’d like a Ultra Super Deluxe Choco-Plutium Butter Filled CupKooky,” a pony said. A tear fell down her face. “I’ll savor it, Leader, I swear!”

“Plutium-95 or 97?” Pinkie Pie said, smiling with teeth so white Twilight could hear them gleam.

“Well—”

“97 has sprinkles!”

It was 97, then. The pony was funneled to the back and another flowed in to fill the space.

“I’ll have a JokeCream Cupcake, please,” said the next pony. “And—Oh, Pinkie Pie, your cakes mean the world to me, more precious than my own foals—”

“You got it, mister! Two bits.”

Money and cake changed hoofs.

“I’ll take a JokeCream Cupcake!”

“Hmm…three bits!”

Twilight blinked.

More JokeCream Cupcake orders followed. Every time, Pinkie Pie charged a different price. Different items were ordered, but nothing was priced the same as itself. Pinkie Pie didn’t name a consistent price for anything.

Twilight couldn’t take any more of it. Pushing, shoving and teleporting her way to the front, drawing angry complaints, Twilight stood in front of Pinkie Pie.

“Pinkie!” she said, hopping behind the counter. “What is going on? Why is Sugarcube Corner going out of business? I thought it was your dream to have a Sugarcube Corner on every corner in Equestria!”

Pinkie Pie put a hoof to her chin. “You know, it’s the funniest thing. It’s like I woke up this morning and the money just wasn’t there! So we’re having a big closing sale. Then it’s over. No more Sugarcube Corner.”

Hearing Pinkie Pie talk in such a cavalier way about the loss of her store brought unexpected tears to Twilight’s eyes. Sugarcube Corner had been such a reliable provider of cake and coffee in the morning[1], and it was Pinkie Pie’s way of making friends with everypony. She couldn’t imagine Ponyville without the giant glass cubes on every corner.

[1] And in the evening…and sometimes for lunch, but Twilight wasn’t going to admit it.

“Don’t worry about me, Twilight,” Pinkie Pie said, beaming, but this time there was a note of sadness to her words. “I’ll just work for Applejack until I can start my new venture. It’ll be a party store. Balloons, confetti, masks and things. You can be my first investor!”

“I…I don’t think that will work…Pinkie! Why are you losing money?”

“Oh, I don’t know much about that sort of thing. I always thought that if my cakes were good enough to bring ponies together, they’d also be good enough to make money.”

So that’s two of them who don’t know a thing about price theory. Just how do they stay in business?

“I…I might have an idea about how you could be making more money. Or at least why you’re losing money.”

“Oooh! Let me guess: more buttercream?”

“No…no…Pinkie,” Twilight said, and there was a little voice inside Twilight’s head telling her that she was about to pull the rug out from under the universe, but she ignored it and said, “You can’t charge a different price each time for the same good. You just can’t.”

“Why not?”

Twilight cast a meaningful glance behind her at the impatient customers.

“Everypony think about your favorite kind of icing,” Pinkie Pie instructed the impatient ponies behind them. At once they obeyed, and the background clangor became excited variations on the theme of “Chocolate, you can’t beat chocolate,” and “Of course a chocolate eater would think about beating others. Vanilla is pure, like the ponies who eat it!”

“What are you talking about?” Pinkie Pie said. “Having the same price every time would be boring!”

(“Strawberry is the best icing! It is pink, like the Leader!”)

“Maybe for you, but it would also be better for your bottom line.”

(“Oh, again with the strawberry, will you shut up about strawberry?”)

“You mean…the amount of money I make selling a cupcake has something to do with making money? That’s crazy!” said the leader of the local pastry cult.

(The room was thick with tension; there were now three factions, the Chocolates, the Vanillas, and the Strawberries, and among them two major philosophical systems, those who saw the universe as inherently tending toward buttercream, and those who saw it as tending toward cream cheese. They watched each other, and themselves, suspicious of traitors, daring any to make the first move to the deadlier of the baking utensils behind the toppings and food dyes.)

“No….” Twilight tried to concentrate. It was hard: She could feel the eyes burning into the back of her head, trying to determine if she was with the Chocolates or not. “Pinkie Pie, it goes like this….”

What followed was a familiar conversation about the role of prices in allocating scarce resources…

…Pinkie Pie seemed to understand eventually….

“How do I find that price anyway?” she said. “It sounds neat!”

“Set marginal revenue equal to marginal cost and then it’s simple.”

“Okay, thanks!!!”

Twilight wished her friend good luck, grabbed a few cupcakes for the road, and teleported out. She had an economist’s hunch that she should talk to Rarity, Rainbow Dash, and Fluttershy before the day was over.

And meanwhile, still inside the Sugarcube Corner:

“Marginal what? Hey, what did any of that mean? Hold on, I’m getting your cupcakes! And stop crying!”

Twilight stared up at the beautifully draped banner reading “Carousel Boutique’s Final Week! Come and weep at la mort du petit cheval!” And below it, in tiny glittering letters, “La nuit, tous les chevaux sont gris.”

And beside it, at the window, a pony plummeting out, hurtling to the ground, a scream of regret tearing from her lips—

Author's Notes:

The story of Pinkie Pie's cutie mark will come later. For now, enjoy Rarity's....