Looking at California: http://bit.ly/1eFevxA And Japan: http://bit.ly/19ZXwbJ I don't see any roads in Japan that are nearly as straight as I-5.
The places where this would make sense have destinations fairly far apart, but not too far apart, with somewhat amenable landscape between them. The Midwest would work, Australia, Russia. Probably Brazil, Argentina? Probably a bunch of connections in Africa or maybe the Mideast... but that wouldn't work for other reasons. East coast seems a bit cramped.