I think as with everything, when you get wrapped up in a community for an extended period and it becomes a big part of what you do in your downtime you end up getting to know people and thus caring about their opinions/views. Everyone wants to be accepted and nobody wants to be on the wrong end of the joke/jab.
Pilot has the right of it really. Plenty of people get heated over discussions and people doing dumb shit but very rarely do I see that extend beyond the server anymore - not the way it used to when everything was taken as a personal attack rather than a disagreement/meme on the forums.