When I visit Asia, it’s common to see people wearing face masks. I’m told it’s considered be polite to wear a mask if you have a cold. So you may just be seeing someone from Asia with a cold. Or a paranoid American.

and often wonder if THEY have a cough or flu, so they're protecting others.

It's the same sort of thinking as "cover your mouth when you sneeze/cough/etc.", just with a cheap medical mask to help you do that, especially if your hands aren't free.

It's most common among Asian communities, but it's filtered out a bit more widely as people think "that's not a bad idea."

Hardly everybody, of course, as you saw, but some.

I've seen more than that in Tulsa during flu season.

There was a report on local news that the masks ar pretty much useless for that purpose.

and some protection is better than nothing

* Masks do not catch all germs - only a percentage at best if properly fitted. Mostly good for stopping floating vapor containing germs from coughs and sneezes.
* Masks do not protect the eyes, one of the most vulnerable parts of our exposure.
* Poorly fitted or incorrectly sized masks provide a false sense of security and invite taking risks.
* People mostly pick up germs from hand contact, then rub them onto sensitive parts of the body (especially eyes) or transmit them into food or drinks.

Our highest risk at this time is the flu bug.

KY..........

incubation period.

Not really surprised some are taking the precaution.

people avoid disastrous medical emergencies.

*mind over matter, some things help even if they have no physical effect on our well-being