Great question, and welcome to MOC.
I'm right with you with the coat pocket, and hangar thing. I do exactly that.
About when you don't have a jacket, I'm speaking to you not from experience, but in anticipation for what i'll do, I suppose, since the stall is private, you could lie it on your leg, and just keep a hand on it... would be relatively safe, but (considering you're already carrying, this should be normal) just be sure to be aware at all times of where it is.
Another thing to do - now I've never heard of the hammock method, but another thing i'd do, is when i'm sitting, just place the weapon between my ankles and keep about my business.