That would be the best way for an escrow of useless tokens, especially ones which involve the developers themselves since they are in control of the smart contracts of their very own tokens.

But if this happens, it means the project is as worthless as their tokens. So there's not much to lose in this situation. If they cheat even in their bounties, that is very low of them. I cannot see how they would succeed when they would even cheat a tiny amount from the people who are very much part of their larger community.