Blacktop and whitetop

Asphalt

Concrete

Why are sidewalks and driveways made of concrete, but publicly owned streets are much more typically made of asphalt? What does this say about private and public goods and priorities? Are we building the public environment on the cheap, yet are willing to invest in concrete for private goods? Prof Richard de Neufville at MIT uses this as example of the effect of Discount Rate on decisions. He argues if interest rates are higher, the future matters less, so first cost is more important, while if rates are lower, costs in the out-years matter more. He also points out that capital subsidies (as in the Interstate program) warp local decisions to choose investments with higher first costs (i.e. concrete) compared with asphalt. Back to the first paragraph, I suspect local governments are more concerned with first costs than downstream, i.e. they have a high discount rate, while private homeowners internalize those costs when deciding on driveways. This doesn't explain sidewalks though, which are typically provided by developers (as are local streets).