Heilein's fantasy, which is about humans migrating to other planets after destroying this one, is just that--pure fantasy. Capitalist ideologists like to think of everything as disposable, but they are deluding themselves if they think they can just drop the Earth into a garbage can and move on.
... unregulated capitalism is one of the greatest forces of destruction of peoples, animal and plant life, and the Earth’s ecology. The book shows that for short-term profit, capitalists are willing to destroy irreplaceable resources. Future profitability is not important to them.This also implies another delusion--that capitalism can be regulated for the interest of all and the survival of all. It's like asking a drunken alcoholic to behave himself/herself. Capitalism delivers the drugs and power to a few who are so addicted that they are uncontrollable. Unfortunately, they are also very powerful! It is only by the elimination of the source of their drugs that humanity can survive.