Reanimation is fun to toy with. Especially when you've got a dead necromancer and several of black soul gems to fill up.
Besides, they need to suffer many deaths for the trouble they've caused. Traven had to sacrifice himself and that filled colossal gem is stuck in my inventory forever, and that's bad. We '360 players don't get to organize our inventories as well as you PC guys do with the mods that deal with it.
But the staff is a real awesome tool, whether its torture, or filling up soul gems with grand souls. And it's also fun to see and fallen foe go against his friend.