Why nobody wants to pay for poor people's medical care

I got a form letter from Columbia-St. Mary's today, the group that runs St. Mary's Hospital, informing me that they have billed my insurance company for my recent stay with them.

18 days hospitalization, 3 of them in med-surg ICU, don't know if bill includes the surgeon: $66,619.56

Back when I was working that would be three year's gross income!
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