I think that it's a very complex issue but I think on many other forums it's about having another life that is not your own.
People seem to like the anonimity of the net and it means that they can shout and be rude to be people or just talk about things they can't or would not talk about face to face.
On here and Britchopper it's pretty calm but many other sites are infested with mindless twaddle and insults.
I think it reflects society and the fact that for the majority of people they find their life is not what they wanted it to be but don't have the strength of character to do something about it so inflict that frustration onto others.
Over the past 15 years through a series of life changing situations I've had to sit and keep my mouth shut and ears switched on to people behaving in an appaling manner and not react and also look at myself and make changes.
Not reacting is probably the hardest thing to do when you would normally be offended by someones comment but you learn it does not really matter what anyone else thinks.... Just what you think.
To Paraphrase a famous quote by someone or other.
"Is it better to say nothing and let people think you are an idiot or open your mouth and remove all doubt"
As for the sex side of things..... Who knows??? I'd rather be doing it than talking about it!