Do you bounty hunters get paid in ETH or do you receive the ICO token (which is erc20 in most cases)?
I suggest you to read the bounty Whitepaper, by doing so you will see what coin they would pay to bounty hunters if it is bitcoin, ethereum or their own tokens. Most of the bounties are ethereum base or erc20 which means you will received tokens as their payment after their project ends.
Suppose you receive it in their own token, I assume you cannot do anything with them until they get listed on an exchange, correct?
Correct answer. No listed in exchange site then that means there's nothing we can do as you mention.