There has been so many projects that succeeded without engaging in bounties.
There is No doubt saying that bounties have their own positive impacts on projects but projects; but most bounty hunters do shalow jobs and expect been rewarded for that.

I have gone through some contents created by people and comments made on this forum; some of us couldn't even express themselves in good English, how much more showing and displaying tact and intelligence in their engagements of the process.

To your question; as long as bounties still yield the needed impact and as long as there is no monopoly in the  organisation of ICO campaigne, bounty hunting will always thrive.