Here's the relevant excerpt from Fresh Cup - the Voice of the Speciality Beverage Industry February 2006.

"Why Wi-fi? Pros and cons of a wireless cafe" by Kristine Hansen.

Some people in the industry , however, see no problem with offering free wireless Internet access, believing that if a customer can pay for a mocha and owns a laptop, they can probably order a second drink, too.

Dave Olson, minister of marketing at Zhonka, in Olympia, Wash, sell DSL Internet connections to a variety of companies (mostly cafes) in Olympia and throughout the Pacific Northwest. Cafe managers then turn around and offer wireless Internet to their coffee and tea sipping customers at no cost. "For us, it's a good marketing ploy," he says. "It promotes us in the community and puts out a lot of marketing goodwill. A year or so ago, it was mostly pay-per-use. Now people are drifting more toward doing the free thing."

With an Internet line and a piece of hardware that processes the signal, cafes can be up and running in no time. The initial set-up cost is between $30 and $50, according to Olson.

He believes pay-per-use Internet access turns customers off because they have to spend time entering their credit card information onto a home page and might have to make immediate decisions about the number of minutes or months they want to subscribe. Also, the fee to jump on the Internet might seem silly to some people when they have plunked down money for a mocha and pastry, and perhaps plugged a parking meter for the time they are in the cafe. "You're already in there paying for premium beverage and a place to sit," says Olson.

There is more but it is a little lame and misleading so ya gotta buy it to read it ;-).