[Phileosopher]

The US has something like this already with cellular with MVNOs, driven by the free market.

The TL;DR is that the cost of cell towers is mostly the same irrespective of bandwidth (e.g., hiring a technician to break-fix as parts fail from weather conditions), so carriers figured out they could "rent" their leftover bandwidth.

Most of the "cheap" carriers are simply slinging together MVNOs from all the carriers (e.g., Boost Mobile, MetroPCS). It creates a weird situation where you get plenty of signal on off-peak hours and (often) the middle of nowhere, but at the expense of having no signal in larger metro areas at peak hours.