Every other place I frequent, be it motorcycle boards, tech boards, whatever trolls are removed. Some of the more fun admins have shadow ban settings where they are the only ones that can see their posts so they can troll on but nobody sees them.
Here, although against the 'rules' it seems to be permitted.
As others have pointed out unless certain lines are crossed, they get to stay. I guess page views are more important the quality.
fxsurfer/snowshow started his trolling career on the biggest Croatian forum (forum.hr) at least 5 years ago but they are not so hesitant to ban obvious ban evaders/trolls so he gets banned as soon as someone spots his new account. In the end he started avoiding it and instead focused on bitcointalk where on top of having bigger audience he can get away with one alt account after another, even though its obvious who is behind them.
I don't know, but you can't register in forum again if IP address connected with your banned account is used again.
Hm care to share some proof of that as somehow I doubt it given all the ban evasion that is going on. And do you mean you literally can't register, or there is that evil fee thing if you try to create new account?