I remember joining my first bounty campaign which I gave a lot of time and effort only to find out it was just a scammed project in the end.  Participants were so mad and throwing trash talks at that time, and as a newbie, of course I wouldn't really know what was happening then.  I even asked them to be patient and just wait for the manager's announcement for further information before jumping in to conclusions.  But then I was wrong, it was really a scam.  That was my experience and that I guessed really happens.  Have a good day!