Why? I'd join more book clubs if I didn't have to spend so much time working or looking for work. And I'm luckier than most in that I somewhat got to pursue a career of my choice. I think the vast overwhelming majority of people don't get much fulfillment from their vocation at all, and given a basic income, would spend their time and energy on "economically useless" endeavors that aren't just wireheading. In fact, I think the degree to which people do that now has mostly to do with feeling trapped and isolated by economic conditions that are a political choice already, let alone in a supposedly post-scarcity world