Hospitals cannot refuse treatment ba
There are places like St. Jude's Children's Hospital that specialize in children's cancers and such, and are funded entirely by donations. I don't know how hard it is to get in, though. And there are certain conditions that make you qualify for government programs like MedicAid and SSI that will help.
Hospitals take cash and credit cards. Insurance is just another way of paying. Not the only way of paying.