What else is there to talk about? Weather? Sports?
Ugh, I'd rather not talk to people if we're not going to talk about something worthwhile.
Not every conversation you have can be about some deep, world-affecting issue, nor is every topic under the sun appropriate for every social situation. If you never want to do anything but discuss srs bzns topics, most people are generally going to see you as being boring, and not much fun to be around. If you find someone in class you think is interesting, why not start off by sticking to talking about why the professor sucks, or a good movie you've seen recently? Save the heavier stuff for the people you know who generally share your views, or who have differing views but are open to having a civil discussion about them. One of the main reasons why my online group of friends has managed to remain close for so long is because we generally steer clear of potentially-divisive topics, or else treat them in a more lighthearted matter. That way, we avoid coming into conflict over petty ideological differences. (Hell, we once had a two-hour conversation that consisted of nothing but replacing random words in movie/TV/song titles with the word "ass." It was glorious.)
The bottom line here is that most people see their personal political and religious views (particularly, I think, the latter) as being major factors in their fundamental definition of themselves as human beings. You may disagree with that sentiment yourself, but it doesn't change the fact that it generally holds true. When you flat-out insult or disparage these views, it's akin to personally insulting that person's own worth, which produces a predictably-negative reaction. I think that the occasional lack of recognition of this by all of us has been the main contributor to the flare-ups that GenDisc has experienced over the years.