Live and work in New York, Paris, or another large centralised city with good (I assume?) public transport? Crazy to own a car, just walk, bike, or take public transport.
however, living where I do in Perth, it is a massively decentralized community with a tiny city centre and huge tracts of suburban living. Very few people live in the city centre, it is primarily a business district only, and so while taking public transport into the city is fine, it can take a LOT longer than a car even with traffic if you live a good way out of the city, and if you aren't going into the city, the public transport isn't great, and a car is a near necessity.
It is hugely silly to label cars as ALWAYS being unnecessary, just as it is hugely silly to label them as always being necessary. It is, like most things, dependent upon your personal circumstnaces.