I run a forum. It is incredibly hard to find a balance between opinion and irrational and inflammatory posts. I have banned a stalker (male), someone who persistently posted racial jokes that caused two of our nicest members to leave (male), someone who was sending vile pms to various people (female) and someone (male) who kept telling me that they had been receiving death threats from our oldest male member, a kindly 90 year old male who wouldn't hurt a fly. I have refused to ban people for political reasons, but been sorely tempted. They have usually cleared off and given up anyway. Ditto religious ones who have tried to convert us. We are beyond redemption I fear. 
But it is what makes a board lively, if we all agreed, how boring it would be. When the liveliest members are away on holiday the boards feels unnaturally quiet and I find I am looking elsewhere for stimulation. So now we have two joke threads, one for normal jokes, one for risque ones. Headings that warn 'If you don't like **, don't read this thread. That sort of thing. If I really dislike something I can change it or delete it before anyone else sees it and tell the member off. Or warn them that we perhaps have more gay members than they had realised... without naming names of course. And astonished by members wanting me to ban people for 'offensive grammar and spelling'!
Our board is far smaller than this so takes far less time to see what is going on, but we have lost our main source of members since the Beeb closed its boards so I fear that at some point we shall all just die off.
If there's one thing that I have learnt, it's that it is very possible to read a sentence in entirely the wrong way from which it was intended. So if you don't like something you see, please read it very carefully before you complain. And if it's late at night, read it again the next morning. I have lost count of the number of posts I made that were taken in entirely the wrong light.