I think it could be serious reputation on the bounty managers, specially if he has built enough trust in the community and probably maybe ruin by just one bounty he manages which suddenly change everything at the end.
That's the problem -- lot of people just don't want to change anything and they just can't quit the bounty. Because of greediness I believe.
If you see the bounty is scamming you just get an ice cream as a consolation prize and leave that crap project alone.