I think it could be a terrible PR move. If you effectively pay your employees less and justify by giving them discounts. A program that begins with good intentions could end badly. Especially if the program is conceived in an era of high profits. In low profits, management makes different decisions. Also, you often get new management.
I meant you run into problems when you end up effectively paying them less and justifying via a larger discount.
Management could end up doing this gradually as times get tough. For example, a company announces lay offs and pay cuts, but softens the blow with a larger discount.
I guess I'm recommending caution. I would avoid making a discount a major part of employee compensation. A worker deciding to apply for jobs at Walmart and Costco could end up weighing a better health plan against a higher discount on basic goods. That seems problematic to me.