Well, OK. The system doesn't work perfectly, but that isn't surprising. You do occasionally see ugly behaviour around here, and sometimes from people who've been around a long time. I note that you've been visiting the site for a week and a half, and I think I know the thread you mean - that kind of overt argument is unusual. I'd been visiting PM almost daily for several months before I became aware of those personal animosities that do exist.

Generally speaking, politeness is highly prized on PM. As far as noderep goes, take a longer view. This node, for example (one of my favourites), has a rep at time of writing of 309. Conversely, I have a node somewhere that gained a couple of votes after I had struck out the text and put in an update saying my answer to the OP was wrong. Assumably this was because people were voting up adherence to local rules (don't leave a wrong answer in a thread, edit and correct it for posterity). The 'final' rep of that node is something like 3 or 4, which I guess (rightly) places it firmly down the bottom end of the noderep distribution curve. So sometimes nodes pick up a few votes for reasons other than correctness.

Many monks, myself among them, are very reluctant to downvote nodes, and of course some people are less tolerant of mistakes & rudeness than others, so nodes that are borderline obnoxious often get a few votes. But they are never going to be in really big numbers.