There are thousands of mixed-use commercial development where employees/owners live above there retail shop.
Many decades ago, in many cities and towns, it was common for the residence to he above or behind a retail storefront. But I think it was normally the owners of the stores who lived there, as opposed to hired help living on the premises.
I can see complaints from employees if this happened. Assuming rent was withheld from paychecks, they would complain they were working for starvation wages etc.