Many bounty campaign give token..often token bounty has not been paid .. you already exist in the market .. after the price paid it down drastically ... if we hold the token .. later will be able to rise or even added down the price of token bounty
Majority of ICO's experience nowadays drop in the price as soon as they hit the exchanges, mostly because of the whole market being in downtrend last 3 months.
A lot of people who participated in bounties wan't to sell them, also early investors who bought on pre-sale with huge bonus, also be dropping the price.
What bring new coin back to life is listings on huge exchanges like binance and other from top 5, more trading volume is always good for a coin and can boost the price for sure.
Trying to look long term on your bounty rewards is also a good idea. Take a look at Stratis or Waves for example, booth needed at least 1.5 years to show significant grow, but who held the coins all this time was definitely happy.
Don't sell your bounty reward all at once, sell partly, and wait for the project to develop a product and enter more exchanges, most likely it will help to sell with more profit.