I think a big part of these bunkers is just that these folks have SO much money they can afford to spend millions or hundreds of millions just in case. And part

I think a big part of these bunkers is just that these folks have SO much money they can afford to spend millions or hundreds of millions just in case. And part of making it so "nice" is that it's not really a "get a text about the world ending in Cali and hop a flight to Hawaii" it's "get a text about anything in Hawaii and drive to the bunker." I'm sure the main estate has security and amenities too, but in some sort of eat-the-rich social disturbance, geographic isolation is extraordinarily valuable. To your last point, I think the long game is actually the same as all the typical end of the world movies and fantastical zombie apocalypse things - just survive. Assuming some sort of societal collapse, regardless of how long it lasts, the idea is just to survive another day and that's going to be a hell of a lot easier behind some thick concrete walls in an island in the middle of the Pacific than it is in suburban California.