Catalytic Converter? We Don't Need No Catalytic Converter!

Many older vehicles are not required to have catalytic converters, or much other emissions equipment.

Why does the government not require these older cars to meet current emission standards?

Simply put, they are a dying breed. Most pre-cat cars (pre-78) that do survive today are not daily drivers. Not to mention, the emissions from all of the non-catalyzed vehicles can't hold a candle to a coal burning power plant.