walk in the store
when they ask you to put on a mask, say no thank you.
If they say "you need a mask", ask them if they want you to leave.
They will usually repeat the verse "you need a mask", but they do not ask you to leave.
I have done tis multiple times, they do not stop me from purchasing my items. I thank them and walk out.
If they ask me to leave, I say, no problem, my money goes with me.
It really is very easy anons.