Wear one if you want to. There would be no or a least less arguement about wearing them if the science for doing so was stronger.

I have cut out all but essential in store shopping since I have been told to wear a mask in shops. We also have to do a lot of contact tracing too in the UK. I'm not a conspiracy theorist by any means, I just don't want the state knowing what I am up to and where I've been, I don't even like opening my curtains.

If you want me to spend money at your business, the rules are, no masks, no contact tracing. Your call.