I'm not suggesting that you're doing something wrong the minute you pull out your laptop. I don't think anybody is. It's all about how much of the finite seating resource is consumed for how much business. Somewhere down-thread is another comment about the purchase price for a cup of coffee being only partly about the coffee but mostly about the experience. Yes, and that's just as true for the person who only needs to sit down for ten minutes. They paid just as much for their coffee as the person who has been there all afternoon, they have just as much right to enjoy that experience, but all-afternoon guy is effectively crowding out dozens of such others. That's simply not fair.

I'm generally not affected by this myself, BTW. I don't go to coffee shops very often, and have only brought my laptop (sans power supply) a few times. The longest I've stayed has probably been a bit more than an hour. I've done more "squatting" at my local McDonalds, which has better WiFi and is practically empty in the mid-morning so nobody cares. However, I consider it a basic rule that if somebody else is waiting for something and you've had your turn then you should yield. If you don't feel that you've had your own fair turn yet, then by all means make the newcomer wait. No problem at all. This is only about the people who seem to feel that they're above that basic rule.