When you ask a serious question, why do people on yahoo answers like to give stupid answers?

Seriously people ask a f*ing question and you get smart *** answers. I hate that. I hate the people on here who think its funny to do that. Like if I wanted those answers, I would say something along the lines of "Hey, a*hole answers only please?". So can some of these people tell me why you like to waste your energy moving your fingers giving a pointless and sometimes offensive answer to someone's real question?