There is a small but growing movement known as "voluntary simplicity," which is founded on the belief in a simple life of working less and spending less. Do Americans who belong to this movement follow the principle of rational choice?
It depends on whether they produce more than they consume. If they have surplus production, then it would definitely be rational.
Yes. Everybody consumes more than they should today. It is not rational to live a lifestyle that is unsustainable, so these "voluntary simplicity" people have the most rational approach.
It depends on their utility function. If they value the uses of their time spent in "voluntary simplicity," it would definitely be rational.
No. It is not rational to live this way because they are not maximizing benefits and minimizing costs. If they consumed more they would increase their benefits.