I can view this in two different perspectives.  I have participated in such bounties like this, that after some weeks of promotion, the team added another.  It depends on the hunter, if you see prospect in such bounty, it's an opportunity to gather more of such tokens, but if there is none, then it's better stop and find another promising project to join.  There are some that will pay at the end of the day and some will be waste of time and other resources.  Mycros bounty campaign lasted for more than a year and few people were able to finish it.  Though I didn't know what they got from it because I didn't participate.  So it all depends on the hunter's view of the project if it is good to continue or not.