There are a ton of unanswered questions and there is no incentive for many people to dig through those. It is extremelly annoying to see that I myself posted a couple of (hopefully valid) questions that nobody cares about because (almost) everyone is in for farming reputation and picking on the easy to answer questions.
I got the bounty idea but, still, bounty or no bounty, it seems wrong to equal in rep a question that was answered in 10s and a question that was answered after 1 week.
A way to differentiate would be to get some extra rep for the questions that were answered after a while. Still this should not be significant enough so that it does not get exploited.