Maybe bounty hunters can learn schemes that are often used by fraudsters so they won't be fooled if there is something similar. For example, websites that look unprofessional, whitepapers copied from other projects, fake teams, etc.

Even if a project is listed on the exchange, it is not a guarantee that it is a legitimate project. It could be just a trap, especially if the exchange has a bad reputation. Patterns like this can be a lesson for bounty hunters to be more rational and not expect too high. The market can be manipulated.