The problem lies in translation of text online.
You can't tell if someone is being sincere or just trolling sometimes..
that's not saying you can't ever tell.. but it is hard.
The policing part by admins can become sticky as well. You get too "gestapo" like, and you drive away the sincere people that enjoy the free speech
atmosphere.
The trolls have been, are and will be around till humans gasp their final breath.

