Not seeing the connection here. Knives are useful. I live in area that has the occasional breaking and entering, and home invasions. My dad has several guns, for reasons of his own.
If we're talking about killing pets, animals, eating people- then I could connect that to horror movie bad habits (or more likely, just being a socio- or psychopath).
If anything, I've learned good habits from horror movies. Check your backseat before getting into your car, lock your door(s) before going to bed, don't pick up hitchhikers, if you here weird noises don't going wandering about in the dark screaming "HELLO? ANYBODY THERE?" Always have situational awareness in unfamiliar places, if you're going to go someplace weird, let people know your itinerary.