[sleazybae]

>can't arrest someone for being drunk and having their car keys in their pocket

yes you can, at least in Florida. i had to recently take a driving class to avoid points on my license, and one of the points the instructor really impressed on that class was that IF you're in the parking lot in your car, (asleep or awake, doesn't matter) AND a police officer stops you AND gives you a sobriety test AND your BAC is over the limit, you're getting cited for sure.

be responsible and get an uber or a lyft or a taxi or any of the other options available to you.