Scorpius the Allfather
Dream Theater fanatic/ghost
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As I said, I could be wrong. My example though is someone smoking and then going to see a movie so driving is not imminent.You can't sit in a car and drink afaik. I've always heard there's an assumption of imminent driving which officers can use too enforce. I could be very wrong, but I'm certain the owner of a parking structure aren't going to want folks using in the parking lot for legal reasons.
How that works out I'm not qualified to hazard a guess.