If the same government making the demand is the one paying for the highway then I agree. But big government forcing small (perhaps broke) governments to spend more money may or may not work out that well.
This doesn't sound like that - plus governments could make money on this investment leasing out the lines. I am curious though - how many "new" highways does the fed build these days. I'd have to think not many. Thats not to say they couldn't do this on "re-work" projects - IE: rebuilds and whatnot where they are already diggin' in.
Then again, most of the big "dig in" projects are likely not rural in nature. Rural roads then to get a new layer of blacktop - not a large re-work of the road.
-Chak