I know someone who works for a large grocery chain. They wear a shield because they have breathing issues and can't wear a mask. Doctors note and company nurse approved.

Now they get called into their managers office and get told to watch out because there is some middle aged white guy running around reporting staff (apparently he gets money for reporting). He demanded the shield be removed and the employee wear a mask...well he didn't and he saw the guy as he went back on the floor and the guy freaked out.

Fast forward a few days and the police show up with health and safety and demand the employee wear a mask. The supervisor tells them he can't and they tell him if he doesn't mask up the store will be fined because "he could be spreading covid and shouldn't be handling groceries". They report back to the nurse and the nurse actually stands up for the employee and tells them no. No fines were issued and they went away which is interesting since if they were really scared of a virus they would have done something.