On a more serious note; How much further is society going to allow this kind of thing? Hiding behind templated e-mails without any explanation. Disrupting people's lives who become collateral damage with no way out.
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.