What would you suggest Save On Foods management do to prevent others from leaving?

An employee needs to see that the manager of dept actually cares about his ir her job, set an example for the employees....otherwise, employees don't show initiative because the managers don't.
Pay increase as the store managers expect employees to work super fast, and get a lot done on short shifts.
Attitudes also need improvement in order to keep staff. When I first started, I had a supervisor that employees were slightly afraid of. She treated some employees very poorly. Thankfully she has transferred to a different location. Treat employees with respect!

Improve the pay for the work being done. 50 lb boxes of wine .... for minimum wage?

Allow them to transfer to their nearby locations

Treat there staff like human beings