Some people might simply enjoy the ritual, I could see that. They love drinking coffee and enjoying the outdoors, why not put them together?
Probably, some of those people can’t just be without something in their hand. Something in front of them when near other people, or it’s like a crutch for an insecurity.
Reminds me of people having to smoke a cigarette.
I remember when I moved to Michigan a lot of the young men would bring their drinks onto the dance floor, which is flat out not allowed in any bar I used to go to growing up in DC. A lot of those guys wouldn’t even go to the dance floor without a few drinks already in them.
I think the question is are they uncomfortable if they don’t have the drink in their hand?