1) Your TCO (Total Cost of Ownership) for a cheap used car can't be $100/month. If you look at Kelley Blue Book or similar websites, they'll tell you that even super cheap cars like that 2005 Ford Focus will still cost you $300-400/month, all included.
2) I almost died in a car accident two years ago, and a result, I value car security way more than before, which means I wouldn't mind paying $35,000 for a very safe car (assuming I'll be able to afford it).
3) Salaries and wealth are not evenly distributed. Something that looks expensive to you, doesn't for someone else.