No, this won't be about some stupid idiom. 

It's funny how all driving laws are thrown out the window as soon as we pull into a parking lot.  There's no speed limit, stop signs are optional, lines mean nothing.  It's a free-for-all.  It might have something to do with the fact that no human being in the history of the universe has ever gotten pulled over in a parking lot.  Cops generally stick to the roads.  Sure, we all understand that the same rules that apply to roads also apply to parking lots.  But I personally don't know a single persons who demonstrates any amount of lawfulness while driving in a parking lot.