Yes, I don’t suppose there are cities in America that are both walkable and cheap enough that a jazz fan could own a small commercial property for this purpose (if they didn’t get rich from something else before).

Seems like a possibility in smaller European cities though.

Hm, maybe! I guess depends on the European city as well? It's like a perfect balance for Japan where the average age is very old, so a lot of retirees who just sip a cup of coffee for a couple of hours. But also, a cultural acceptance of flying solo, sitting by yourself at a table, basically doing nothing and listening until it's your time to go home.

To be fair though, all the places I went to were much less busier than actual local bars or designated cafes. A couple of places were just full of regulars (I went to a couple of them multiple times, and it was exactly the same people) with clienteles with average age of 60+. Obviously I have extremely limited amount of data points, so might be very wrong.