[Alberta's Child]

Heavy, dense loads like dry and liquid bulk commodities are among the few loads that are economical to ship over distances less than 400 miles in a train. The higher weight capacity of the railroad offsets the inefficiencies of transloading the cargo.

Maritime shipping is an even more obvious example of this. It probably costs less to move a ton of cargo 5,000 miles across the ocean than truck it 50 miles up the road. It's all about the economies of scale of the transport mode.

[a fool in paradise]

This article discussed a proposed truck only interstate system. Not 50 mile hauls.