You make a good point. Yahoo! absolutely should recognize quality questions--and quality answers. Top Contributor badges leave as quickly as they come--once one gets back to answering in assorted categories, there goes the badge.
The big problem, lately, is that questioners are not going back to select their own best answers to their questions, and this results in the questions going into voting. The problem there, is that many of the voters only read the first answer or two, and select one of them (when actually answer #12 could have been the thorough, factual, even researched answer).
In lower levels, it does pay to ask as few questions as possible, as one is trying to reach enough points to get to the next level (where he or she can ask and answer more). Some top contributors are in lower levels, and are trying to reach higher ones. So, they answer, vote, sign in every day, and try to get best answers.
I only started asking questions when I reached a level where questions and answers were unlimited. To tell you the truth, I ask a lot now--but have a real tough time trying to think up questions that have not already been asked a million times.
Again, you have made a strong point, and a good one. At the bottom of this page, under the flags, you will see a link to '...tell us what you think...'--I think that you should give that a shot. I haven't a clue as to how long it would take for staff to get back to you on it, but it is worth waiting for. :)