Reportedly over 9000 Covid cases in the US are health care workers.
Some of whom haven't had access to N95 masks, some have been banned from using their own masks, some have been encouraged to use bandannas or other improv masks.
Every weekend, I've asked my parents in NJ about mask wearing, and initially they said the Costco workers weren't wearing masks, with many saying that it was because they couldn't get them. But I think still today Costco cashiers in NJ aren't wearing masks. They installed plexiglass barriers. I'd want plastic barriers, masks and gloves. And actually even under those conditions I wouldn't do such work. Cashiers interact with too many people.
I'm not sure how payment works in the US these days. At least most people don't use unclean money. But it would be best if your credit card can simply be scanned or you can swipe it yourself, so no on else needs to touch your card. In Shanghai, I pay for everything via a phone app for the past nearly 3 years. No cash, no cards. No contact at all. Quite safe in these days of disease.