It's fine to get on a bus or get in a taxi while drunk, I don't see any reason a 100% autonomous car should be any different... in theory. The dilemma here is can the person take control of the vehicle?

Being able to get hammered, and then pass out in the back seat of your car while it drives you home is the dream. But in the slim chance it does get into an accident, there needs to be a way to prove you really were blacked out in the backseat, and the car crashed on its own. And not that you drunkenly grabbed the wheel and tried to do a u-turn to McDonald's.

I wouldn't call a car self-driving if the occupant needs to be involved.

Unfortunately marketing has figured out that "self-driving car" is the next cool thing, so they're rebranding driving assist technologies as "self-driving".

(I am aware of the definition of different "levels" of self-driving cars; from my perspective, that's marketing. Either the car drives itself, or it does not.)