why would I drink if I'm not driving?

Why? So I have a second carabiner to grab depending on if I'm driving or not? Or I can take my carabiner (car keys, house keys, bike keys, pepper spray, and hair ties) every time I leave my home and never accidentally grab the wrong keys. It's not a concern to bring the car key to the bar if the car is at home.

it's how they cope with their miserable life.

a lot of people are not full blown alcoholics, but alcohol dependents, as if they don't get shit faced, but they need a drink to function in ordinary situations.

I have known people like this. They can't interact without people without alcohol. So at work, at a party, or just getting a coffee... they have to drink. And most stealth way to do this is a nip they can drop in their coffee or whatever. Typically they are not drunk or visible intoxicated, but without drinking they feel anxious and miserable.

it's called Alcohol Use Disorder, or if you go by the alcoholic stages, it's stage 1-2 on that scale.

My favorite is the people who come up with a cup, an energy drink and ask for some shots. On their way in to work. You’re not slick.