Actually most US city interstates may carpool lane, not a total apprehension of cars who don't carpool.

Meaning, may specific lane for cars with 3 or more passengers, parang "express" path, while the others will have to ply with the rest of the traffic sa normal road.

Think of one lane being totally free of traffic jam, smooth flowing 50-60kph traffic while the main 2-3 lanes are clogged bumper-to-bumper.

Pero I think mahirap din uubra yan sa pinas... US states usually disallow dark tints up front anyway.