[danielrpa]

That would be okay with me if we could actually get to this level of granularity. Same thing for the streets used by public transportation? Subways alone won't work everywhere, so we'll need buses, and these will need highways too and pay for them in the fare.

I think most governments decided that it's not practical to get to this level of granularity, instead trying to get the cost closer to the user. For instance, having vehicle licensing and gas taxes paying for streets and highways in general based on usage statistics. For electric vehicles, governments are studying approaches like charging by mile driven using tracking devices (has its own problems).

But in my earlier proposal, getting the costs closer to the user would mean for trains and subways to pay for their own tracks and energy, and buses to pay for their streets and highways through licensing and gas (and for special bus lanes directly through tickets)