> "Would you consider paying more if he would personally help you fix it by modifying your code?"

He or she, really. Personally, I find the "please fix my code [paste large amount of code here]" questions on StackOverflow to be of little value to the community as a whole. I don't mind answering them, but if I look at my own profile (which is a fairly high ~17k rep) my answers that have been most well received/up-voted are almost universally problems that have been abstracted away from "fix teh code" type questions.

In a way, bounties are already a kind of payment, if you consider reputation to be a currency of sorts (and I would).