Your information is outdated. It was unafforadable fifteen years ago . . . in the last five to ten, it has become very, very affordable and has exploded in popularity to the point that it's available all over the country. Here's one example: https://atlas.md/wichita/our-fees/
Children 0-19 years old, $10/month with at least one parent membership
Adults 20-44 years old, $50/month
Adults 45-64 years old, $75/month
Adults 65+ years old, $100/month
Employer groups with 5+ employees, $50/mo/adult
That particular practice offers wholesale-priced labs and meds as part of the price (which is common), which can save you more than the entire cost of the membership if you're dealing with something chronic. https://atlas.md/wichita/benefits/
I don't have a dog in this fight — I was merely pointing out that no one is stopping non-rich people from buying anything. It's just that people with lots of money can afford more than people with less money, in medicine as in anything.