I think the reason behind that is that it's a new place and people are shy in new environments. Not only they behave more cautious but they lurk more (which leads to more lurking by others).
Yes, I'm a bit of a moron, but I still want to be fair. In every single community I read the same comment on and on again. It goes something like this:
People in name_of_community are x.
With its obvious variation
name_of_community is y.
That always sounds to me both strange and nonsensical. Every large set of beings is, obviously, large. We're always sampling it from a very biased perspective. You may be unlucky in your interactions; or perhaps you're more tactful; or you've connected in a very bad day; etc., etc., etc.. So saying that name_of_community is y is just a Quixotian attack on a windmill.
If that gets you high, elated, if it makes you feel better about yourself because you're not like them, please go ahead and keep enjoying yourself. But also remember you're riding an beaten old horse, wearing a rusty armor, and talking nonsense.