You won't be able to buy it at that price. Sure, I got it for $2 too, but that was only because it was on sale. You'll have to wait until around July for Steam to get on sale again.
You know what would be absolutely epic? A virtual game for this that modeled situations well. I would spend hours on that, but unfortunately all of the games that try to depict this kind of situation is much too unrealistic.
But anyways, Bitcoin is an online currency. I'd think that actual, physical currency would be a lot better for your little island.
Both are excellent, but I'd have to choose pizza over hamburgers. Of course, it definitely varies with the brand and whether or not I get fries with it.