There's an important thing to realize about FU money: it does not make telling people to fuck off cost-free. Telling someone to fuck off is an indulgence, and it is not free of cost no matter how much money you have. Having FU money simply means you can afford this indulgence. But one of the many problems that comes from having this kind of money is that now you have to make this choice. When you can't afford something, it's a no-brainer. When you can afford it, you actually have to think about it and take responsibility for the result of your decision.