Under no circumstances should real money be allowed to be involved; let them play for the sake of the game. True enthusiasts and professionals know what that means. Otherwise, greed will creep in, which is not a good thing, even if there is some goal involved. The goal is simply to have a good time (I'm not saying – with benefit).
In my opinion, Heroes are truly self-sufficient. It's not up to us to change them, and there's no need to.
Auto-translated
