I live in Minneapolis - I see it all the time. Several times a day in fact. I still see people in outside settings wearing them as well. By now, if I see a person wearing one my only two thoughts are: a) this is an act of virtue signaling (Minneapolis is a VERY progressive city) or b) you are immunocompromised and or wearing it for medical or health reasons.

Since both of these are on opposite ends of the spectrum, I just hope its for medical reasons and being cautious as opposed to the former and get one with my day.