basically it just makes sense that you let people socialize on the presumption that sales will occur because you have a well liked product
https://en.wikipedia.org/wiki/Coffeehouse
Basically the concern about "open to hosting non customers though" involves with asshole management, or customers abusing the privilege but taking up space used by paying customers for long periods of time
for example:
I didn't see anything in there about coffeehouses gladly hosting non customers, but I didn't fully read it either. I've never heard of businesses openly promoting such a policy either.
I'm trying to see the other side of this, but it still doesn't make sense. If I were sitting there without buying anything, I wouldn't be surprised if they asked me to leave, and I would either buy something or leave. It never would reach the point of police involvement. Failing to leave private property when asked makes you fundamentally guilty.
probably makes a difference if they have wait staff or not.
no wait staff? then they are not policing people who come in and hangout and chill. Just a practical thing.
You're definitely right that coffee shops have a long tradition for hosting intellectual discussions (e.g. cafe culture in Vienna or Scotish Enlightenment). I never assumed they have historically been open to hosting non customers though. Do you have sources or more information I could read about this precedent?