If they don't or rarely, accept insurance, then I am guessing the vast majority of people can't conceivable afford their services.

I mean if I need a series of surgeries that going to cost say 30k, along with a year of physical therapy and various prescription meds to recover, let's say somwhere in the neighborhood of 40k total cost for the whole shebang....if I am told "Hey, there's this place that will do it for 23k rather than 30k, but they don't take insurance so you have to pay for all of it yourself".....that doesn't really help me. It might as well cost 500K and be done on the moon for all that helps me. I still can't even remotely afford that, and I would have to go with the overall more expensive, but less expensive directly to me, insurance option somewhere else.

The problem is that healthcare just cost too damn much, I would love to live in a world where insurance was only needed for occasional rare catastrophic medical conditions, and that most citizens could pay for most medical expenses out of their own regular income.

That is the world I would like to live in, but that is not the world we occupy. We occupy a world where you have to be pretty damn well off to have even a reasonable shot at affording care out of your own pocket, even at places like the Oklahoma Surgery Center, and the overwhelming majority of people have utterly no hope of affording medical expensive stuff without insurance, making them a neccesity.