No real "lines", but years ago I was shopping at a QFC and one of the checkout cashiers was attractive. While waiting in line, I saw that the store provided a sheet of paper and pen asking if there was anything you wanted but couldn't find in the store. I put down that I wanted her phone number and handed it to her when she started checking my groceries. She wrote her number down, we dated for a while.
Also picked up a gal once at HER bachelorette party at Shenanigan's in Spokane. Went to my hotel room, messed around a little, but didn't cross any lines. Don't remember what I said that made her go to my room. She was hot too.