Lordy how I emphasize brother. 105+ here for the last month. And no B&M's within a 2 hour drive to smoke at for me.
I have traveled extensively in the last 4 years and been in B&M's all over the place without any problems. I can't say that I have ever asked 'Mind if I smoke my own?' But I also always will buy at least one or two when I come in until I get to know the owner. Maybe you should pick a B&M you like and become a regular.
Or you could drive down to Tucson and go to Anthony's as I know they won't mind. Just don't ask them to put on the Sun Devil's game.