Don't be so sure. In a lot of places the infrastructure is already there.

When I first got cable internet (seems like ages ago) I lived in a small city that got it's cable piped in by microwave tower. The speed was good but packet loss was a big issue any time it rained or snowed. To fix the problem fiber was layed. The cities population at the time was about 23,000 (with several thousand more in the surrounding rural area) but they layed enough cable (fiber I imagine) to bring full cable and 10Mbps service to about 2 million users (or so I was told)...and at the time 1Mbps was damn fast.