You're wrong. Because almost all projects indicate such an item. The team can change the rules at any time. What does this mean? That the law of law does not help here.
Team can't change contract after bounty. There are rules that they can change contract during bounty but that raise legit questions too, lowering rewards in middle of ICO and sending lower rewards to bounty participants can only be applied to rewards after this was changed but every other reward before it was changed should be what was arranged in original contract.