WiFi services as a marketing tool

In the New York Times of March 04 2007 Randall Stross compares WiFi-services offered by coffee places, bookstores, McDonalds, and the like with air-conditioning offered by movie theaters when air-conditioning was not yet available in most homes in the USA.
The economic question is: Why are WiFi-services sometimes free when some, such as Starbucks, charge for the service?
The problem is a nice one for Barzel's theory of property rights (Barzel, Y. 1997. Economic analysis of property rights. 2nd ed. Cambidge UP). Barzel distinguishes between economic and legal property rights. Legal rights are the rights the state assigns to a person. An economic right, in contrast, is the ability of an individual to enjoy a piece of property. Moreover, a property right is usually defined not for a single thing but for a bundle of attributes of a good. The bundle can be undundled, re-bundeled, as the seller sees fit. When you buy a cup of coffee at Starbucks you also buy the right to use their free sugar, sit down on an empty chair (you don't buy the right to tell some other customers who are already there to bugger off), but you don't buy the right to use their WiFi-services. For that you have to buy an access card, in addition to the coffee. At other places, you buy the right to sit down and to use the WiFi together with the coffee, hamburger, donut, or whatever.

The important point is: Coffee shops , like movie theaters, are selling several rights but leave some in the public domain: Airconditioned movie theatres sell enterainment and the comfort of a chair in a chilled place but leave the chill of the foyer in the public domain. Coffee shops sell coffee, but leave the right to use their sugar, to sit on chair, to use the bathroom, and, perhaps access to their WiFi, in the public domain. How they define their product, i.e which rights they bundle together and which they leave in the public domain, is a matter of cost and of demand and the question for the shop owner who considers whether or not WiFi services should be sold or left in the public domain for all patrons to use for free is: What is the impact on revenue? The cost of providing WiFi are unaffected by the decsion - but revenue may be affected by it. Some sellers, such as Starbucks where the shops are usually full, will decide to sell WiFi services, whereas others, with fewer customers and unused seating capacity, may decide to leave WiFi in the public domain in order to attract more business for their remaining products or servcies.

RAEM