Applejack and Pinkie Pie don't mind looking up to see Fluttershy flying in the sky,

or knowing that Rainbow Dash can rest on soft, fluffy, comfortable pillows while they can't,

or seeing bright, flashing lights that blind and burn their eyes when Twilight perform spells,

or knowing that Rarity can carry things and teleport without lifting a hoof while THEY need to lift THEIR hooves to do that.

Nope, they don't mind knowing that they can't do those things. Not one bit.

But when Discord get's rid of their friend's wings and horns before they head into a maze, and he doesn't take ANYTHING away from them, and their friends freak out, knowing they can't do those things now.

The two earth ponies start realizing some things.

Some very, VERY, VERY interesting things.