I don't think it is. Sidecar Health is doing just fine on this model[1]

It's pretty perverse that you, an insured person, would have to lie about having insurance because the provider would charge you more for being insured.

[1] https://cost.sidecarhealth.com

The same goes for pharmacies. Walmart advertises $4 generics. If your insurance has a $25 drug co-pay, then they will charge you the full $25.

I do this. Once my insurance company got upset that my procedure was so expensive and rang the hospital. The hospital immediately tripled the price. The insurance became even more upset and asked me to fix it. Still much cheaper than the equivalent procedure in the USA.

It's not illegal here, but in any case nobody asks, I just tell them I'm paying cash.

It's not insurance. They're "fixed indemnity plans." Sidecar Health is the one I'm familiar with.

https://www.brookings.edu/blog/usc-brookings-schaeffer-on-he... (Fixed indemnity health coverage is a problematic form of “junk insurance”)

Health care consumers are absolutely free to pay providers directly even if they carry insurance coverage.

They could be running as a "health spending account" where you can spend the money on whatever you want provided it's health-related. You don't technically have "insurance" but you're insured.