runner my entire life and have always run without a shirt. My dad ran without a shirt as did every guy and most of the girls on my high school cross country team. This was in Southern California. I always figured it was normal.
I have only had someone yell "put a shirt on" to me once in the 25 or so years I've been doing this. It was a dude yelling from his car as he drove by when I was a BYU student in Provo.
Once a teenage girl yelled "put some shoes on!". That was funny.