If your entire city is designed for cars, and there are some buses that sit in traffic with everyone else, I'm not surprised that people buy cars. It doesn't mean that's what they want - it's just the only option.
In the end I think viable alternatives should be available. I think it's stupid to drive 15 miles into a city on the same 8 lane highway as everyone when 1 or 2 train tracks could meet the same demand and function (and a streetcar/subway/walk for the rest of the journey).
I do not think cars shouldn't exist. I think they're completely necessary for tons of people at the moment, but I think we should invest in other options that are working extremely well in other places.