The problem is that developers can name any amount in which they value their tokens allocated to the bounty campaign. This figure can be 10 000 and 100 000 and even a million. However, in the end it can decrease hundreds of times. Therefore, the bounty campaign should be chosen primarily for the project, so that its tokens are able to grow in price. Understand that? After all, you can promise any amount, but the main thing is that the project was able to fulfill its promise.
They can promise any amount to the bounty hunters. But in the end, the rewards that a bounty hunter is going to receive will depend on the success of the project. If a project is a successful one, then the campaign participant can easily convert his tokens to either fiat currency or BTC/ETH using any of the major exchanges. But in case the project fails, then the bounty hunter will be left with a few useless tokens in his ERC-20 wallet, which is virtually worthless. The campaign manager can claim that he had paid out the rewards as promised. But the bounty hunter is left high and dry here. His work has gone unrewarded.