Recently, a question was asked on SO and the user who posted it also posted two answers. Both the question and answers gained both up and down votes. In total, he gained (according to his profile) 120 rep points and lost 22 rep points. The question was then subsequently closed as "not a real question". This means that in the 4 minutes the question was open, the user gained almost 100 reputation points.
It seems to me that because upvotes can significantly outweigh downvotes, there is no real dis-incentive to posting junk questions that will almost certainly be closed a short time later, but in the meantime will gain a user potentially significant reputation, especially so if they also add answers to their own question which get votes.
Could this problem be tackled in some way? Perhaps when a question is closed (only as spam/not a question?), any positive reputation is recalculated to give it a lesser (or even no) weight?