If you only need 8 hours of work from a worker, then find someone looking only for part time work. They're out there.

The problem is there are millions of people working 40 hours a week or more , sometimes at multiple jobs, who still can't afford to guarantee they and their families eat 3 healthy meals a day or go to the doctor.

Look at the increase in worker productivity since the 70s and then look at the lethargic growth in worker compensation. Those two variables should be tightly coupled.