...People that are not using the service should not have to pay for it just because someone decided to run a line past their house. That would just encourage the planners to run dark fiber everywhere and collect fees for years before people decide to connect.
There's little reason to charge by the bit or have data caps like most ISP's do. It's not a finite resource like water is. The major cost is last mile, once you have that in place it is a minor cost to upgrade your backbone to support extra usage. The last thing parents need is a huge bill because their kids watched a ton of 1080p youtube videos last month, downloaded a lot of games off steam, or whatever else. The penalty would either be so small that it would be meaningless to have at all or big enough that it would cause massive bills by surprise like cell phone service and smartphone app pricing have done in the past.
I don't think you are taking economic realities into account. I modeled my proposal on the local water company. It costs money to run the fibre past each house. Somebody has to pay for that, and who better than the owners of the houses. Having this source of revenue encourages the utility to run fibre along each street, not just the wealthy neighborhoods. They wouldn't get paid for truly “dark fibre” only for fibre which can be connected to and provide Internet access.
Yes, data communication is a finite resource. It costs money to send a bit reliably across town or around the world—lots of people work hard to make sure the Internet stays up. Who better to pay those costs than the people who want that bit moved?
If parents don't want to monitor their children's (or guests') Internet activity, they can ask the utility to cap their daily data volume to prevent unpleasant surprises. There are other solutions, more difficult technically but not beyond reason. For example, the traffic of children and guests could be marked so that it could be limited in badnwidth and daily volume.