I've worked in retail for most of my life.
You honestly cant win when it comes to the general public.
If you are wearing one, customers get annoyed that they can't hear you. There are also customers with some hard of hearing elderly and ones with hearing difficulty. It's becoming an obstacle for them in day to day life which most people don't have to worry about.
If you aren't, you get verbally attacked by people for not wearing one.
Also god forbid you are the poor unfortunate soul at the door checking everyone is wearing a mask. I've seen colleagues shouted at, sworn at and some customers threaten them with their jobs, push past them to get into the store. All for not wearing a piece of cloth on their face for 10 minutes.
Also bear in mind, people in shops have used their glove free hands to stack the shelves, take unwanted clothes from the fitting rooms back to the racks, scan your goods into the till etc. Masks are no guarantee of protection in shops, so much more gets handled. Of course workers wash their hands and have the alcohol gel, but again no guarantee of protection.
It's funny no one was complaining that workers in supermarkets and corner shops weren't wearing masks in full lockdown. Now it seems to be a childish tit for that, I have to wear one so you should have to as well.
I don't really know what my aim is with this reply. Just to make you more aware of what it's like on the other side I guess. Please give retail workers a break. Like I said, you really can't please everybody. For every person that gets upset that you aren't wearing a mask, there will be someone that gets upset that you are, or that they have to.