I agree with that. There's one US city where it's completely normal and ordinary not to own a car. There are maybe a dozen others where, if you live and work in a relatively central area of the city, you can probably get by without one without too much hardship. Go much beyond that and you may be able to get off without one but a lot of things get harder and you have to compromise on your activities.

18 cities have >25% households without a car. 8-9% of households lack cars.

http://www.governing.com/gov-data/car-ownership-numbers-of-v...

Yes, much less than 100 cities. I live in the Phoenix area, and can't imagine how hard it would be without a car. It's so spread out that it isn't funny. I have a car mostly because I like driving, but still would have one if I didn't, just not the same kind of car.

I also feel like a certain number of those people are carless not by choice but because they cannot afford a car, and are putting up with a pretty extreme level of inconvenience.