I want to clarify some things before this turns into a bashing sessions around how we are terrible bounty managers and allowing 'hackers' to join our bounty.
* We have over 50k people participating is any number of ongoing campaigns, and as much as we would like to check everyone, unfortunately we cannot. Like most, we do the best we can. Since there are no good API's for BTT or automated solution, our team isn't able to vet in detail every profile of every bounty participant. When someone reports something that COULD be an issue, we address it until we figure it out.
That's the managers faults. You choose to accept that many participates. You choose to ignore who signs up, and look to this as an excuse. Ultimately, if you are managing something you should be manually checking everyone that enters to assure that they are a suitable candidate.
You shouldn't be relying on others to report it for you. You should be making an initial assessment, and then checking periodically on all members. This is why large amounts of people that aren't distributed via the work force isn't a good idea.