The majority of bounty campaigns are only introducing spam on bitcointalk. So, I hope they're not going to be here for long.
They are ran by weak managers and don't care about quality or keeping the forum a good place to find useful information.
Partly agree with you, as still there are a lot of new projects that control the quality of work of the engaged bounty hunters.
Rules like "make not more than 3 posts a day" and "spread your comments over the entire week" are gaining increasing popularity.
It is a natural evolution process that might really improve the situation with spamming and low-quality work.