Necromancy gets a bad rep.
Oh, sure, some ponies like the whole cliche of the evil zombie master, pulling his puppet strings to make corpses dance and kill for their amusement. And yeah, you kinda do have to work with dead bodies a lot, and most ponies find that a bit creepy. Oh, and you learn a lot of spells to kill things and gain power from it.
But, come on, that doesn't mean all necromancers are bad... right?