I find it contradictory to the concept of upvoting that someone finds a question worthy of an answer, yet unworthy of an upvote.
I get the impression that it is a bit egotistical to not even care to upvote. I also get the impression that these are point seekers, who care little about evaluating and awarding credit where credit is due.
As a longtime SO user, I believe that it would be only fair to award 1 upvote per answer (and deter the answerer from downvoting the question, naturally).
if (question_is_answered) UpVoteQuestion();
However it might cause unexpected consequences.