It is indeed a nice question, who is going to pay for wireless cities? Technology Review provides a good discussion of this issue.

One reason cities and towns appear eager to leap into the wireless fray is the inclination—and pressure—to serve their constituents. "Local governments very much want to be more citizen-friendly," says Joe Pisciot. (...) The wrinkle in the public-service spin on Wi-Fi is who will bear the cost for the service. The answer splits proponents into two camps, and both are problematic. On one side are those who see wireless broadband as a public amenity—a basic service that cities and towns should provide free to residents as they do, say, trash pickup. (...) In the other camp are those who eye Wi-Fi as a potential revenue generator. Proponents of this model say cities and towns could negotiate affordable residential Wi-Fi rates as part of the bundle of wireless broadband services they purchase for local government departments, such as fire, police, and schools. (...) "A town can make any argument it wants," says Frezza. "It has as much money as it can pull out of its taxpayers."