There are several types of coatings used for the striping of crosswalks, street lines and parking lots.
Most parking lots and some streets used to be painted with an oil based paint that is sprayed on. Lately due to environmental issues, most people have switched to a latex based paint.
Roads and other high traffic areas are usually striped with a thermoplastic. The plastic is melted in vats and poured or spread carefully onto the road surface using calibrated dispensers.
Some places use a thermo set tape which is places on hot asphalt and fuses to the surface.

What you saw was probably thermoplastic, which I think is too brittle to use as a skin coating.