In which case the global economy is dead and there’s no one to buy their work?
you only need people's money if you can't control their labor.
did a plantation owner in the 1600s need the money of his slaves ?
if you control a robot that can fight and take over land, enslave workers for things robots are bad at, harvest food, create buildings etc. what do you need other people for ? your entertainment? robots can do that too.