Is this actually acceptable practice?
There was a recent question where a user basically stated in a comment that they were going to downvote a question because the questioner wouldn't (or didn't know how to) accept this user's answer. Lo and behold, there's a downvote on the question even though there's nothing that I can see wrong with the question.
I understand everyone has the freedom to do as they like, but I was under the assumption that votes were used to describe a good question or a bad question, or a non-vote for a meh question. Are votes to be used as leverage as well? You don't scratch my back, I'll cut yours? Not only is this blatant rep-whoring, but it seems to me to undermine the structure of SE.
I can totally understand when someone doesn't accept your answer even though you spent time to help them. I totally understand that the questioner should accept a solid answer. But if we take this to its logical end, what's to stop users from going through and downvoting everything that another user's done, simply out of spite?