The St. Cloud, Flor., network was likely the first free citywide network: The small, but at that time rapidly growing Florida community brought in free Wi-Fi for a variety of reasons, one of which was sold as keeping dollars local. Money that was spent on broadband left the community, it was argued.
Three years into the network, however, the city doesn't want to continue to commit funds to something that only a fraction (however large) of the population uses. With 32,000 residents, and over 10,000 households, spending $600,000 a year for perhaps a 1 in 3 or 1 in 4 user base may not be the right allocation of funds. The city will keep using the network for municipal purposes.
The current mayor, elected after the one who pioneered the project, wasn't so hot on the network in 2007, but voted against shutting it down.
As an early deployed network, St. Cloud hit a lot of snags in teaching people how to use the network and installing hardware. Every antenna had to be replaced at one point (apparently not at the city's cost) due to a manufacturing defect that may have affected only some of those installed.
The only other free networks that were intended to cover cities were never fully deployed. MetroFi was offering a mixed free with ads/fee to remove ads network in several cities, but was unable to complete any full deployments in larger towns.