Exactly-- and I don't think it's just structural. A lifestyle of killing sentients and taking their stuff might or might not be a pleasure in the real world, but it seems to satisfy the imagination.

Women's Work: The First 20,000 Years Women, Cloth, and Society in Early Times is about what can be deduced about the early tech whose products don't survive for millennia.

Even then, people were looking to fill time as well as to use it.

You'd think people would evolve towards maximum-reproduction utilitarianism, but I'm not seeing it happen.