You have a right to blame the bounty manager if the amount of money is less form your expectation. I mean, you took an instance with different cases, 1 dollar will have the same value because the dollar price is not have volatility price. Different with cryptocurrency which is have a high volatility, I won't blame bounty manager if the payment for each bounty hunter is $500 and the bounty manager will send the amount of token which have the same value to $500 whatever the amount of the token.
I am saying if someone is to blame that is company or team. I did not say bounty manager is guilty as they can't do anything if company decide to lower rewards so BM can't be blamed. It is not important how much is something worth, signing contract for one amount of tokens should give you that number of tokens which you agreed to be payed in and team agreed to pay you. Each bounty has its own set of rules and each one should be looked at in a different way. If it happens that team wants to send less tokens for only reason because bounty hunter will receive too much money when they exchange tokens to fiat, that is scamming bounty hunters and breaking a deal, of course, it has nothing to do with bounty manager, neither bounty hunters or bounty managers are to be blamed.