I have done some bounty campaigns that were unsuccessful.. Also some were scams. But I have received some tokens from few of that projects. So I need to know this, Is there any opportunity that can I use this tokens? 
The only opportunity you have with them is when there is a buyer, but if there is none it's stuck to your wallet or better create a wallet for your useless coins so it will not become an eyesore whenever you check your wallet balances.