The canonical example is person A buys some risque item, their partner sees the credit card statement says "what is this?", so then person A denies they made the purchase (because they are embarrassed), says it must be fraud, so then it gets charged back on the credit card.

They do not have SMS OTP confirmation for bank card purchases? It is much more difficult to deny anything when there is a record of delivered SMS message along with phone identifier and precise location.