I've seen people do this, and my first thought is "what happens when the waiter brings him something he's allergic to?" The patron didn't make the conscious decision to order that specific food, which makes me think the restaurant is now open to a lawsuit. If I were the waiter in that scenario, I'd ask the patron if he's allergic to any of the foods the restaurant serves, which would probably ruin his ego depletion game but would at least cover the restaurant (hopefully) if he then succumbs to his dinner.