They've state repeatedly that this is a profitable enterprise for them. As a public company, they couldn't say that if it weren't true.
“Google received stunning regulatory concessions and incentives from local governments, including free access to virtually everything the city owns or controls: rights of way, central office space, power, interconnections with anchor institutions, marketing and direct mail, and office space for Google employees.”
http://bgr.com/2012/09/10/google-fiber-criticism-crony-capit...
maybe they're profitable but that's not going to last or others (Comcast, AT&T etc) will sue the government for favoring Google over them.
Even if they said it's profitable, it all depends. Maybe some of the costs are shifted from division to division within Google. Either way, just because they said so, doesn't mean there isn't some wiggle room. They cannot lie about total sales and revenues, but many companies do not even break down division sales.
Surely you realize that local governments have been doing this in all sorts of industries.
The give property tax abatements to WalMart or sales tax abatements for equipment deployed in a data center within their borders. This is nothing new.
And like someone else mentioned, TWC and Comcast have had de-facto monopolies for the past 20-30 years. Cable companies are bound by a franchise agreement with the city. One of the things they agree to in that agreement is that they have non-exclusive access to the market via the public right-of-way.
Also consider that one of the things cities will do is try to get ANYTHING that will bring jobs and industry/investment to their community. Growing the tax base is a prime directive of any city.