I wouldn't be surprised if a significant number of people here do this. I do this as well. Most of the time, I'm not asked to leave, but other times, if I feel guilty, I buy something else, like another coffee or a sweet. I suppose I'd willing to "rent" space if it were available. A funny relevant anecdote. Yesterday, I was at home trying to work, and I could not focus, so I walked to a nearby coffeeshop. Apparently,…
If there's a point where a significant portion of a community become knowledge workers, then it would be advantageous for local coffee shops to adapt to a co-working atmosphere. It wouldn't surprise me if a chain such as Starbucks did something like this in the future.
When I was working remotely and in-between jobs, I regularly squatted and rotated through coffee shops in town. What sucked about this though was several things: buying food/coffee out of guilt because it seemed like the right thing to do, constantly packing-up and unpacking your gear when going to the restroom, holding your bladder in as long as possible because it's an annoying and expensive context-switch to tend to one's biological functions, and uncomfortable seating which isn't meant for prolonged use.
Coffee shops in college towns will mostly be immune to this because it's simply how students live and work. Au Coquelet and People's Coffee in Berkeley come to mind. Talk about laptop brigades! The Berkeley Public Library wasn't so bad either, and they had free Wifi.
Nowadays, co-working spaces seem to be popping up everywhere now. Even where I'm at now in Lancaster, PA, which isn't exactly a tech hotbed, there are already 3 co-working spaces. I'm at the point now where coffee shop squatting is just too much of a hassle and would rather pay to have a quiet working environment that forces productivity, provides a solid Internet connection, offers decent amenities, and offers controlled access so I don't have to worry about getting my laptop stolen when stepping away from the desk.