That's where we are going with Capitalism. In 500 years when we had improved robotics to the point of being able to do most of human work (excepting maybe knowledge work), it will be cheaper to buy a robot than to hire a human.

With more than 20 billion people at that time (the USA could have 850 million ppl), the only way for people to survive will be through hyper-efficient production processes and equalitarian distribution policies.