In Minnesota they have signs that say they are required, but I haven't been wearing one now since last fall, and before that it was barely covering my mouth. Hyvee told me it was their company policy, I told them I couldnt wear one, he said "okay thank you." And kept walking. Other then that I've only been asked one other time. Just try going someplace without one, Minnesota prides it self in being a progressive state, and I've beaten the odds. (Fun fact, our retarded governor was caught in Wisconsin at a restaurant because his own state was shutdown. They are power hungry politicians trying to control you, don't let them win.)