On the flip side, you probably get paid a fraction of a penny more when someone leaves a comment, even if it's generic. That doesn't sound like much, but a comment here, a comment there, and pretty soon you're talking real pennies!
Personally, I don't mind those inane comments too much. I simply don't rely to them. I do my best to respond to any legit comments.
My biggest comment peeve is when people denigrate my writing and/or me because they disagree with me, especially when it's clear there's no real knowledge behind their opinion, just hate. If you disagree with me, use real facts to back up your assertions. Otherwise just go bother someone else.