It's like Barnes & Noble versus previous bookstores. Barnes & Noble encourages you to sit down and read books you have no intention of buying. They're smart enough to know that if you're in the store for 2 hours at a time on a regular basis, you're going to buy SOMETHING. I buy a lot of stuff at Barnes & Noble even though Amazon is generally cheaper. I go there all the time because it's such a cool place to shop, and I buy stuff because I see it and I'm like, "I WANT!"
Anyway, my impression was always that Starbucks and others had the same idea. If you let customers chill for a few hours, they're going to buy stuff. I know I do. If I'm going to sit and read or sit and use a laptop, I'll buy a good drink and some kind of snack. If I want to stay after I finish that, I'll buy something else.
I guess the problem is now customers aren't buying stuff, which sadly coffee shops are fighting in less-than-optimal ways. The problem is, I think, that there is no optimal way that coffee shop owners can do anything. Customers need to be reasonable and support the businesses that are giving them such a nice place to hang out and get online.