Such a service could be offered by the legacy payment providers.
I have used such services in the past, but still feel the field is ripe for disruption.
Most all of them have VISA cards.
Expecting customers to carefully create a wallet, an exchange account (so they can buy the crypto) and considering how difficult that can be (even for technical users) is really unreasonable. When people can use crypto as easily as they can use a credit card, then it would be an alternative.
IMPO, this problem is very similar to the PGP problem. You'll get a lot less email if you only accept PGP encrypted and signed emails. You cannot expect your customers to do that. They won't, but they will send you plaintext emails from their Gmail accounts, just as quickly as they will pay using a VISA card.