What's the problem with answering them? If anda know they're perverted, just don't bother with it! This site is for 13+ for a reason anda know, we can say pretty much whatever we want.
I wish people would. But some say that it's "fun" to do so, atau that "someone has to" but my thoughts are "um, no anda don't, no one is forcing anda too, and if we hate him so much and answering him isn't making him go away, so either we like his presence atau we're not mature enough to walk away."