Sometimes it feels like people always have to find a flaw to latch onto and take some meaningless stand on, no matter how irrelevant. I don't know if it's for the fleeting sense of superiority, for the sake of discussion, or (as you put it) because they take themselves too seriously. I value the importance of criticism, but not when its primary motivations are self-serving.

For what it's worth, this is a phenomenon you see in most tech communities -- it happened on slashdot, proggit, and it's present here too.