No, consumption doesn't fill that need. "The rich will still need the masses to consume the products the rich sell" is a tune that some economists whistle throu

No, consumption doesn't fill that need. "The rich will still need the masses to consume the products the rich sell" is a tune that some economists whistle through the graveyard when they're brave enough to contemplate the end of human labor but not brave enough to contemplate that automation might render most of their discipline obsolete. That said, I don't think that the rich can wage a successful war of extermination against the poor. If we reach the point where human labor is completely obsolete, and any old plutocrat can fab up a robot army, then it's not just exterminationist billionaires who get access to robot armies. It's also philanthropic billionaires, and national or even regional elected leaders, and perhaps even robot "pirates" who are just duplicating robots without permission. That's an existential risk to civilization in that it takes a much smaller group to threaten global violence than it did circa 1940. But it also means that the most a rational Evil Billionaire can hope for is mutually assured destruction; any overtly violent attempt at eliminating the poor can trigger a cataclysmic war, but the EB can't rationally expect to kill off the masses and get away with it unopposed. EB better have already uploaded his backup consciousness to offsite Martian storage before trying that one. (But if he's an immortal being who can live in space, why would EB even want to kill his way to more control of property on Earth? This is like the implausible plot of a bunch of alien invasion stories where societies capable of interstellar travel still want to come here to violently seize our dirt and water, for some reason.)