Pharmacy Benefit Managers (separate from, but mostly vertically integrated with, insurance companies in the US) absolutely have been doing this for years now. It lets them say they're providing a service and reducing prices when they're doing the opposite.

Without getting into the details, the cash price of drug x gets set obscenely high, pharmacies bill this price to the appropriate Pharmacy Benefit Manager who then tells the pharmacy "we're paying you whatever we pay you". By and large you're lucky to break even. For some medications and some contracts it can cost a pharmacy hundreds of dollars to fill a prescription. You're not allowed not to fill it. You're not allowed to charge the patient less than the cash price you charge everyone, which is the inflated number the PBMs conspired to come up with. If you do, you risk losing even more money getting audited by Optum or Express Scripts and good luck with that lol lmao

That's the short/comprehensible version. A 30 count bottle of ondansetron (generic Zofran, nausea med) costs $0.39 or so but the U&C most pharmacies use for billing purposes is >$1,000/30 tabs. Actual reimbursement for #30 ondansetron looks more like $0.39 + maybe a dispensing fee that doesn't cover the cost of keeping the lights on. That U&C also becomes the cash price without goodRx or one of the other middlemen who aggregate PBM data and pick a price more or less at random from what reimbursements actually look like. GoodRx also bills pharmacies $8 for the privilege of checking a price with them, every time you submit them a claim.

It's fucked. There's compounding pharmacies that'll make injectables for you cheaper than you can find at a standard retail pharmacy, if you can find one.