That they're businesses, making a profit from people's suffering. Very often, the care a patient receives is based on what their insurance company will pay, or what the hospital can extort from the family, not what the patient needs.
Two years ago, I went though cancer and major surgery without any insurance. The hospital told me, three days before I was scheduled for surgery, that I had to pay them $30,000 in advance, or they wouldn't allow the operation to be performed. Fortunately, I had already spoken to the financial services department, and knew to tell them I wasn't paying a dime in advance. If I hadn't known to make that call, I would have been turned away, from a surgery that made the difference between me being cancer free today, or dead.
In reality, I ended up paying the hospital about $16,000 for all the ER visits, operations, biopsies, and tests I needed. The hospital didn't really expect me to pay $30,000. They were just trying to scare it out of me, at a very vulnerable time. I'm sure that works sometimes, which is why people end up losing their homes to medical expenses.
I've got no respect for the for-profit hospital system.