The issue in the US seems to be that even if you have a decent insurance plan you can still easily end up getting treatment by someone out of network. An anaesthesiologist or similar.
I wonder how it works if you're wearing a shirt that says "Don't touch me unless you are in network with xyz insurance plan #".
That won't save you. The doctor left the room and did a quick phone consult with a radiologist about your x-ray. Radiologist is out of network, so you'll get a big, fat, separate bill from them.