I think this is largely due to the greater shipping distances (rail gets cheaper relative to trucking as the distances gets greater), and maybe a bit the lack o

I think this is largely due to the greater shipping distances (rail gets cheaper relative to trucking as the distances gets greater), and maybe a bit the lack of interference from passenger rail. Btw, in Europe many networks are state owned, some are privately owned. By open-access regulation forces every track-owner to open their tracks for a fee to other operators. There's also a distinction between track-owners and track-operators, even if a single company may be both.