The same people who are buying products and services right now. Just 10% of the US population is responsible for nearly 50% of consumption.
We are just going to bifurcate even more into the haves and have-nots. Maybe that 10% now becomes responsible for 70+% of consumption and everyone else is fighting for scraps.
It won't be sustainable and we need UBI. A bunch of unemployed, hungry citizens with nothing left to lose is a combo that equals violent revolution.