Why is it health insurance can't pay 100 percent when 80 percent usually leaves most with a huge bill?

One big problem healthcare in my family (married couple, 2 children) is that even when our insurance does pay, it only pays 80 percent, and we are stuck with a huge bill or bills especially after a hospital visit or stay from multiple facilities. I have so many health problems even though I am only 29 that we cannot pay every medical bill that we owe, it is impossible. We pay what we can, but still end up having some go on our credit. Now people with Medicaid, which I do think is wonderful for those who need it, end up not having any left over bills and us people who make 45,000 to 50,000 a year end up with huge bills we cannot ever pay due to our other obligations like house payment and car payments and things for our children, which are much more important than a left 500-600 dollar hospital bill plus multiple others, especially when we basically live paycheck to paycheck anyway. What can be done about this?
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this sounds crazy but you already admit you can not pay all med bills .So if you look up your credit report you are already listed as a risk This is what you do Quit paying any med bill after insurance. This is why for many reasons 1. medical bills generally never hurt your credit scores if you keep up with the rest of your debts 2. every person with a ounce of brains knows what a rip off these bills are 3. The med bills are delibertaly over priced so those who have insurance pay for those who do not have any. 4. when the insurance company pays they get a huge discount that you never see on any of your bills. 5. When my son in law had emergency surgery his tab came to 32,000 dollars. I met with my daughter His wife at the Hospitals accounting office before they checked out.They had no insurance or means to pay the bill so I settled the account for them.I told the lady that I would give them 4000 cash if they would mark the bill paid in full.I gave her 3 minutes to accept or likly never get a cent as the kids had no way of paying. They tried to argue but I told her you have one minute left after that I walk. As I have no responsibility to even offer a settlement take it or get nothing. THEY TOOK IT>>>> You can do the same walk in make a offer show the cash they accept or walk never more to return.or feel obligated to pay. at 15 cents on the dollar they still are making a profit. $20 for a .05 cent asprin proves they are way out of line. Every one has a right to make a profit but not that much or at the risk of your well being ,peace of mind and severe stress it causes your family.
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