The Internet would have to come from somewhere. I am not talking about everyone disconnecting their home service in favor of Google's ( or whoever's) free Internet. Much of the Wifi could be from people's home and business routers. Like Cable vision/Time Warner/etc. it would be available to people who are already subscribers; it is a supplemental extension of their home service. It wouldn't decrease wirleline profits and could potentially increase them as people switch to carriers with the most dense Wifi coverage. Google/NYC/other free WiFis would simply add to that density.