If you add a number to your utility in every possible scenario, it doesn’t change your behavior. So you can treat the parking fee as either a gain that can be had or as a loss that can be avoided, as long as you are consistent.
So the question is, for the other option besides gambling, where he just pays the parking fee, is he treating that as no money gained/lost, just part of the status quo before he made his decision, or is he treating it as a loss? If the former, then waiving the fee is a gain which he can add. If the latter, then waiving it is just a loss averted.
Something to keep in mind is the time cost of playing casino games, and the fact that the casino set up the game so that people would give them money. (Maybe they expect it to reel people in for more than the minimum amount of gambling and you know you are too smart for that, but maybe everyone “knows” that about themselves).
If you add a number to your utility in every possible scenario, it doesn’t change your behavior. So you can treat the parking fee as either a gain that can be had or as a loss that can be avoided, as long as you are consistent.
So the question is, for the other option besides gambling, where he just pays the parking fee, is he treating that as no money gained/lost, just part of the status quo before he made his decision, or is he treating it as a loss? If the former, then waiving the fee is a gain which he can add. If the latter, then waiving it is just a loss averted.
Something to keep in mind is the time cost of playing casino games, and the fact that the casino set up the game so that people would give them money. (Maybe they expect it to reel people in for more than the minimum amount of gambling and you know you are too smart for that, but maybe everyone “knows” that about themselves).