Yeah, it's not the value, it's more of the principle. As in, what harm does it do for them to vote regardless of the size.
I do agree, a good comment is worth it's weight in gold. For those people I tend to advise them that it can be seen as spammy but in the nicest possible way.
The ones in question that I really hate though are the ones which barely relate to the post and are just some generic words slopped together angling for a random upvote on said comment. I find them offensive. Hehe. But I can be a gnarly character.
And who doesn't love a whopper! :0D