That's not what happened at his competitors that invested in workers like Publix and Costco. They were happy enough with their wages and work environment being

That's not what happened at his competitors that invested in workers like Publix and Costco. They were happy enough with their wages and work environment being better than the rest that they stick with the company working hard. The industry has a tracker for customer satisfaction. They're high in it regularly. Your hypothesis didn't play out when management were committed to taking care of employees with a good baseline.