It definitely depended on what walmart. I never masked, stopped at a walmart on my way home from a friends, I was the only one without a muzzle in the sardine-packed place. A manager even tracked me down at the back of the store and to tell me I had to wear one. I told them no, that my health information was none of their business, and just continued shopping as they tried to argue. Everyone was staring at me, and I just laughed, I couldn't fathom their compliance, I still don't.