The privacy of cars and their ability to go door to door can in no way be duplicated by mass transit. If you've got to be stuck in traffic, wouldn't you choose to be able to flick on the air conditioning and the tape deck?
問題是，汽車的私密性與門到門的可及性，絕非公共運輸能及，就算塞車，大家也寧可選擇在自家汽車裡吹冷氣、聽音樂。