I think there's a whole lot of this going on, mostly to reviewers who don't seem as "popular" for one reason or another. In school you had a lot of the popular kids who would make fun of the ones they just plain didn't like. Same thing goes for RIA, when you see "funny" marks on comments that make perfectly good sense (and nothing funny about them), simply because the reviewer who made it was one of the more "unpopular" ones.
But I didn't come to RIA to win a popularity contest. I came to give my opinion, and I have a right to it, popular or not.