So let's say pornhub takes bitcoin (can't check, as I'm in a public place). It still needs a refunds and frauds department for those payments, no?
And pornhub does take credit cards. Yes, the fees are higher. But largely because the chargebacks are more common (spouse finds out, buyer feigns ignorance).
What's SSM in this context?
I don't understand where the issue with refunding crypto should be. It's also way cheaper than what stripe, PayPal or co charges if users issue refunds. Personally I only save money by using crypto, I save thousands of dollars in transaction and chargeback fees every year. For me as merchants it's a non brainer.
I also use crypto as a customer but I usually trust these companies before I send money. The swiss Amazon is accepting crypto for example, as customer I trust them and all customer protections laws apply as well.