)
Celestia has been lied to on the nature of pie and what it is. She does not know and cannot be harshly punished by her ignorance but in the continued entertaining of her behavior is doing nopony any favors. The truth _*has't_* to be broken at some point and it's going to hurt a lot. For this we are have to stage a intervention of her false belief and bring her back to the straight and narrow.