To me the restaurant bill (aka bar bill) is the important one. And some uninformed people don't know why. It's not what's going to happen in the restaurant, it's the dang parking lot or the street you're parked on. It's the walk to and from.
I heard Drake (from Drake & Zeke 98.1 - Memphis) the other day, questioning why this was important and how this would be enforced. Obviously he doesn't know why, and as far as the enforcement, it's just like most other laws - after the fact! Sometimes Drake can be a real condescending idiot. And I swear he's a closet Obama fan. He showed his hand a bit during the election. I know...rant...