The rich often absolutely do want to live in a society that is about that, who do you think “has theirs” and is saying FU you everyone else, in the first place?
But the rich, some of them at least, realize that that is unsustainable, but rather than investing in fixing the problems they've created it's cheaper to buy an exit ticket so they can go create the same unsustainable but beneficial-for-them-in-the-short-term situation somewhere else.
Maybe, but most super-wealthy people/corporations want to profit from such a society, including those in less "FU, I got mine", more socialist societies, like many in Europe. That way they get to enjoy the quality-of-life benefits that come with more redistributive societies while also enjoying the profits that come from the US's environment.
The example that immediately comes to mind are non-US pharmaceutical firms whose business model for developing medication is sometimes predicated on selling them in the US market, with it's unregulated medication prices.
This phenomenon rolls down the increasingly "FU society" hill from the US, too. One need look no further than the US' supporting fascist dictators in Latin America in exchange for more friction-less resource extraction from those countries.
It's a hedge against the fall of American society. Nobody wants to live in a society that's all about FU, I got mine. And the rich have a means to escape it.