Treek & trööt, as you say "trick and treat" in German.
Oh I know you don't, I just find it amusing if someone would believe this.
Two comments I want to say about this:
I've read about something similar, why do not vampires feed on something similar to human blood? The best explanation I've heard is that they would be feeding on some kind of "life force" in the blood, not the blood itself.
The witch thing.. I can feel her pain. When eating animals, it maters what the animal has been feeding on. Bad food for animal causes bad meat. My mother in law has eaten seagull and she said it tasted like fish.