Don’t know of any in Calgary, but I go to all the grocery stores in Cochrane without a mask, finding almost 100% acceptance. Most clerks will engage in conversations, even coming up close beside me to talk. Most customers will do the same, and several state they wish they could go unmasked but don’t like the potential of confrontation. Only once did a senior of about 80 years of age make comment to me about not having a mask on. I responded “no, I don’t” and carried on. At many businesses in Cochrane, only a few clerks ask me if I want a mask (typically those ones are about 20 years of age). I say no thank you and carry on with my business. There have been places where I have left because they won’t serve me, such as MacDonald’s and Coffee Traders, but I have found the majority don’t even ask if they can provide you with a mask – they allow you in and conduct business with you. I’ve not tried Walmart since I refuse to shop there. Maybe one day I will just to browse about.