Locker room at an ice rink, movie theatre during a show, bar bathroom (several times), several bar parking lots, finger blasted a chick on the dance floor, (absolutely hilarious watching her cum and trying to dance), an outdoor couch at this same club, up against a hotel window many times, the slide at a park (high school was fun lol), coffee shop bathroom, public park on a wooden swing, my parents' backyard with a low fence next to a busy street, a very public jogging trail during a weekday afternoon, an apartment complex garden, a couch and table in a Sunday school classroom after hours (going to hell for that one) and parking garages as another poster mentioned.
None of these with providers, but I wanted to give some ideas to my fellow folks with a public fetish