It's pretty crazy how this works. Despite having pretty good coverage, I often use GoodRx because the prices are so much cheaper than using my insurance...
Ha! So I work adjacent to the insurance industry and, hilariously, sometimes tier based copays on medication fills can exceed the pharmacy's price - usually pharmacists will catch this and just never bill the insurer, but sometimes patients can end up paying more for a drug because of their insurance.
Healthcare is all kinds of insane at every level.