As long as they are outside in the woods and not in my house, under my bed pillow, etc. I actually saw one crawl out from underneath my pillow and I FREAKED...THE....FUCK....OUUUT!! So, yeah, nature has to survive, but damnit, it's them before me. SMASH!!
I've never seen a black widow ever in my life. But I can't kill something simply for being a dangerous animal. That's the thinking that has destroyed whole populations of bears, wolves, and sharks.