Its a reasonable question, the challenge is spectrum management. As the city would provide layer 1 (connectivity) not any above layers, they would have to become the spectrum manager for wireless base stations. That is percieved to be too complex. Also this has to meet the needs of consumers and businesses alike. Currently fiber scales from 1mbit > 1TBit [1] so it has that flexibility. Maintenance of the fiber is independent of the special laser you would attach to it if you were say, the new LinkedIn headquarters, versus a consumer.
Not that fiber is particularly "easy", looking over street maps and figuring out what sort of bundles/routing you need to get full coverage is quite an exercise in itself.
If it's too complex for a municipality to manage the right technology, is it the right thing to deploy the only technology they can manage? There are market solutions in place for wireless; and spectrum management is already handled by the FCC (would a municipality even have jurisdiction?)
I guess I remain unconvinced how this is not effectively a subsidy to the media companies (Netflix et. al; including Comcast once they start offering a cable-over-internet product) given that the primary use case of wired high-speed internet access is overwhelmingly streaming video (since over 80% of Internet traffic is streaming video). I also don't imagine it would lower costs significantly over a company like Comcast in the long run; the margins aren't great on a business like that and line maintenance is much more expensive long-term than people realize.
Not that fiber is particularly "easy", looking over street maps and figuring out what sort of bundles/routing you need to get full coverage is quite an exercise in itself.
[1] http://www.lightreading.com/optical/400g-terabit/euronews-bt...