Does anyone know why the healthcare system prefers those with health insurance over those who self pay?

I was going in for my acl surgery this morning, feeling good about having paid dr. lintner $7k in full and arriving early. i arrive to the office 2nd floor/room 800. as i make my way in, a rather large woman relays a message from another woman (on the phone) who was at home using a sick day or something… the message stated that i still owed $13k to the surgery center. that’s already $20k for knee surgery.
then she says i still owe the anesthesiologist an undisclosed amount, which no one seemed to know how much exactly and the anesthesiologist just decided to never answer his phone. anyways what i want to know is who charges $13k for a room for a few hours? dr. lintner has the ability to do the surgery and charges just more than half the amount of a room? if anything the doctor deserves $13k and the room should be, what, $500 tops? not 13 thousands dollars! who set that price? it’s kind of making me feel like i’m dealing with criminals, that’s evil to charge so much for a place of healing! just a place for you to get fixed up and proceed with your life… now i dont know what i’m ganna do to get 13 thousand dollars… i can’t even work with my knee dislocating when i walk. why is it the the room actually costs less when you have insurance? insurance covers the room regardless so why does the price go down for those insured, how does it make sense to do that? why isn’t it cheaper for someone who can’t afford health insurance? i’m afraid i won’t ever be able to fix my leg and i’ll just have to accept this as a part of my new life!
Updates
6 mo
but insurance covers the costs of the $13K room and the cost of my surgery
Does anyone know why the healthcare system prefers those with health insurance over those who self pay?
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