If you are referring to the services being a scam then, try to find a bounty running by TokenMarket, BountyPortal or reputable bounty managers on the forums but If you're speaking about the members impersonating other members then there isn't much that can be done here. If the manager is vigilant, that shouldn't affect the original participant in anyway.
That particular platform that you mention above pays only a penny due to heavy participants. They have no limit in bounty hunters, and that is not right. They should at least make the bounty profitable. I would prefer hunting limited slots bounty campaign than joining automated/over-loaded platform.