I've experienced a form of hostility in StackOverflow just recently--as in a couple of days ago. On a whim, I visited the website and answered a couple questions, something I'd never done before. I realized it was actually a lot of fun, so I started rapidly answering the all JavaScript questions I could as they were asked.
Suddenly a "higher ranking" individual started leaving comments on my answers that I needed to stop answering certain questions, and only address "well asked" questions. After reading the guidelines, I noted that neither I or the asker had broken any rules, so I commented that I felt I was being treated unfairly, and I asked where I could discuss further since the comments on my questions seemed inappropriate.
Suddenly another, even higher scoring person, deleted all the comments and locked my answer, noting that the discussion had stopped being productive. After that, my answers were left alone with no more meta criticism.
In my limited experience, it's a bizarre community.