With Uber, Walmart Plus, whatever, it seems like worrying about tipping, inflated prices, etc makes things too complicated. If you used the service before Amex introduced the credit, value the credit at full value. If you have to start using a service in order to take advantage of the credit, then you already lose utility; you lose even more if you do things like worrying about tipping / not tipping, get frustrating on pricing, start comparing prices across services, etc. For example, Walmart Plus appears to be a useful service, but I don't have a need for it, so I have not signed up for it since Amex introduced the benefit. I may get around to looking at it but it has no bearing on how I value the card. However, Saks, Uber, Equinox, Streaming, etc were all stuff we were using anyway, so the credits work.