Frankly speaking, they don't occur too often in my communities. However, I don't mean to say they have never occurred. Once, when I was running a sports community, a user, who identified as a pagan, started criticizing Christian ideology. Since they had a logic, I thought it was ok, but one of our moderators, who happened to be a devout Christian, felt offended. The staff team voted to warn the user by majority and I had to agree.
How Often Do Dramas Occur in Your Communities?
Drama occurs all the time on the Christian forum that I run!! It actually brings a lot of activity...until people get tired of it and then it comes to a halt and the site is almost dead for a while. Then new drama happens and boom, people return.
I think on some types of forums it's best to have rules that religion and politics shouldn't be discussed!!