For the very reasons you have stated, I would like to see the polling option removed from the forums altogether. I have never seen any good come from them other than the feedback (for which you don't need the poll).
Polls are fine for discussion forums, but serve no purpose in a support forum. Whenever I see a poll on a support forum, my first thought is that someone has a complaint to air. The results are always going to be skewed to the point that they're meaningless.
Maybe just leave the polling option active in the Wish List forum. It makes a lot more sense there.