IMO, the free plan is brilliant. They get people to front the money for putting in infrastructure, and as digital distribution of everything continues to grow, they'll probably start to see people transitioning over to the faster connections. $300 + $70/month is a hard sell for a lot of people, but if my parents could ditch Comcast for a one time fee I'm pretty sure they'd do it.
Once the fiber is there, google can actively offer free demos of cool bandwidth hungry tech , for people, in their homes. what better way to sell more bandwidth and services ?