The reviewer who called this a scam is way off. If the pharmacist had trouble with the coupon, I suspect he/she did not use it for whatever reason, and charged full cost. It would have been nice if the reviewer had identified the store.
We have used goodrx coupons at Target, Walgreens, Kroger, and WalMart, and have gotten the prices shown on the site. We have several elderly cats, and have saved hundreds of dollars on their prescriptions. Yes, you can use these prescriptions for pet medications! Our vet now tells all of her pet owners about the site (no insurance for pet prescriptions!).
Another hint: if you are on Medicare, by law (thank you, Democrats) you can not be offered any incentive, like coupon discounts for co-pays or even Target's 5% off rewards program. We have found many prescriptions are the same cost or cheaper without Medicare (often not even needing the Goodrx coupon). We instruct the pharmacist NOT to use Medicare when processing the prescription, and get the discounts. Using Medicare is not required.