I'm going to guess that you haven't met many mathematicians; in my experience they are always at each other's throats. Indeed, that seems to be a common thread amongst academics of all stripes.
The more knowledgeable we become, it seems, the less tolerant we are of dissenting opinion - which makes some sense, as it becomes rare to meet anyone who can justifiably disagree with you, and common to meet people who are in the grip of Kruger-Dunning syndrome.
I have met many mathematicians - more than any other profession, probably (either that, or second behind lawyers). Cases of hostility like that exist, but are in my experience very rare. That said, that is mostly face to face talk. Perhaps, forums are much worse (in fact, the very few cases of hostility I do know are also on line).
In any case, the sort of hostility encountered here seems to be the norm in forums in which religion and/or politics are discussed, at least leaving aside blogs that belong to professional philosophers, most of which are in my experience much less hostile (but then, most of them are more strongly moderated too, so maybe that's the reason).
At any rate, many potentially interested discussions are precluded here by that hostility, usually due to people behaving in defense of threats to their ideology (we don't usually call them "religions", but they seem to have a lot of similarities), but sometimes, apparently the hostility happens even without that.
