Wifi in most coffee shops is for-pay. Not only for-pay, but you pay directly to the ISP. In Pittsburgh that almost always means Telerama (http://lm.com), and at Starbucks that means T-Mobile (http://tmobile.com/hotspot), except when Telerama tries to put hotspots near Starbucks, then it means war.
That's irrelevant. Both ISPs and Coffee Shops are taking hits here. T-Mobile is the obvious loser here, trying to provide high-availability wifi to a crowd who has some issues.
A comment was heard, "when I go into a coffee shop I pay for the drink and get the comfy chair for free." I think that sums up why coffee shops are so successful. That is, why they're The Hang Out in so many places. The comfy chair is a business expense to keep customers.
I think wifi in coffee shops should also be free. Free as in chair. Long term, the ISPs would do better to provide bandwidth, a gateway, and proper security for a free access point in coffee shops who are willing to pay for the expense. The business expense is simply bandwidth and equipment. The coffee shops stay coffee shops, and the ISPs stay ISPs, just as the current system allows.
This way, when you go into a coffee shop you pay for the drink and you get wifi and a comfy chair for free. Lets be honest, bandwidth isn't that expensive, as a business expense. Proper firewall and throttling rules can ensure that. So, produce a "turn key," drop-in system that can connect to a business class DSL and you've created another incentive for customers to stay and have another drink.