There is something off here: you can use your credit card to buy pornography of the most awful and depraved kinds ,you can use your credit card to place illegal wagers or take part in illegal gambling, you can use your credit card to buy drugs, legal and illegal from illegal or at least dubious sources or to put money at risk in pump and dump schemes and the banks and credit card companies are adamant that they cannot identify and prevent such transactions. And yet, when their own business models are under threat, suddenly they are able to identify and prevent the purchase of cryptocurrencies such as bitcoin, Ethereum and Ripple plus many, many more.