For above mentioned everything forum has to make strict rules for these bounty managers . As far I am seeing big corruption is happening . So please any one in forum admin group please make some rules for bounty manger . Atleas ask them to put some escrow amount for announcing any bounty.
So that they will pick only genuine participants because thier money at risk.
The admin usually does not care about these things and he cannot monitor all the bounties started too, having an union for bounty hunters is a good dream that will not be fulfilled, expect to see regulations being implemented by government that could cripple fraud in this market, other than that there is nothing you could do unless you personally investigate every project and start reviewing.