Even worse, there are sometimes even deceptive statements made about how much you will have to pay, and business arrangements you enter into without even knowing that the other party exists, much less that you're getting their services.
I didn't see a doctor for ten years because I couldn't afford insurance, and when I finally got covered through a decent job and went to get my first general checkup in my adult life, there was a big sign up front saying "ALL CO-PAYS DUE AT TIME OF VISIT". I figured that meant what it said: anything I owed, that was not getting billed to my insurance, was going to be billed to me before I left. When they let me walk out without paying anything, I figured that meant I must not have had a co-pay, which made sense to me as it was just a general physical exam, and a blood draw for some basic general-health lab tests (cholesterol, blood sugar, STDs, etc).
Then I got a bill in the mail a month later. Called and complained, why am I getting billed, didn't my insurance cover this, and THEN they tell me that that bill is for the remainder that's left after what my insurance paid (IOW my copay). I argued about the sign saying all co-pays were due at time of visit and they said... I don't even remember what now, exactly, but something to the extent that that's no excuse and I have to pay the bill. Not knowing what else to do, I did.
A month later I got a different bill for the blood tests, from a different company. I called and complained that I already got a bill for that visit and paid it and even that was unexpected and what the hell is with two different companies trying to collect for the same fucking service. They explained that they are the lab that my doctor sent the blood off to for the tests, and they they bill separately, and that paying my doctor for their service doesn't get me off the hook for the lab service. I had no knowledge that I was even buying services from this lab company: the only entity I interfaced with was my doctor, they hired the fucking lab, let them pay the lab and roll the cost into their bill, I figured. But no, and lab insisted I owed them money, and not knowing what to do, I paid up.
A year later, my second doctor's visit in my adult life, different doctor in a different town as I had since moved. They at least had the decency to say up front how their billing works (without me even asking), and that they will send me a bill for the copay after they process it through my insurance. And they don't do in-house blood draws and send out to a lab, they send you to the lab of your choice with orders for what tests to run. So that's better, much more clear. But the lab itself also has a "ALL CO-PAYS DUE AT TIME OF SERVICES" sign... and this time, they actually billed me at time of services! Awesome. So far, I was liking the medical establishments in this new town a lot better.
Until a month or two later I got a bill from the lab. When I called to complain that I already paid them at the time of services as their sign said, they told me then that that was only an estimated copay, and that after they put the bill through insurance, there was still a balance remaining on my copay, which is what that bill was for. Again, no idea on what grounds to dispute it, so I paid up... but ugh, what the hell
For emergency services where the patient may not have the time or awareness to evaluate the costs and benefits, I can understand you just do the service and bill later. But for a motherfucking general checkup and routine bloodwork? Jesus fucking christ, how can you not just say what it will cost up front and bill before I accept your services?
It's only one step removed from the homeless guy who washes your windows without your consent and then demands you owe him money. "Hey man you need some medical services?" "Yeah uh I guess how much?" "Can't tell you yet now turn your head and cough." "Uh... [cough]" "Aight you cool man, that'll be $100." "WTF no you didn't say it would be that much" "Too late you got the work now you pay the bill man... don't make me go get my collections posse to shake down yo ass, pay up sucka."