Henry Ford realized this a long time ago, whatever his other faults. He both made the car cheap enough, and wages high enough, that his own employees could afford one.
Those days are gone, however, and we’re not talking about cars, we’re talking about food. Walmart employees aren’t paid enough to afford food at their place of employment.
The difference is that Ford couldn’t ship his products overseas. He had to keep his customer base able to buy. Corporations now don’t view the home market as important anymore. They can always get another customer somewhere else who will pay the price. So who cares if their own employees can’t be customers.