How would that break any laws? It's essentially doing a commercial mesh-net of sorts, like many are already doing in Europe and elsewhere.
If instead, they gave you a box and a map - and that box supported wifi - then a mesh network or something would be feasible. Wired could be done by running the wires along the fence or trenching inside the property line (neighbor to neighbor - if your neighbor is willing).
Otherwise, point-to-point mesh wifi (or maybe even free-space optical - like the Ronja system).
Not sure where any of that would be illegal as long as no other carrier's TOS was infringed or such...