With my dick driving me crazy being hard, twitching with need and pre-cumming, I have to jerk off frequently. I also try to do it behind a car door to have some discretion. I have done it in some parking lots though where I can be behind a car doing it with my pants down, shooting my load on the cement.
Brass balls buddy! I've done that, do it fairly often actually, but I generally hide behind an open door or something. Ever been "done" then notice the security camera you had been in front of the whole time? I have. Not so good.