Fraud protection of credit cards is the root of modern e-commerce. In some ways, Visa and Mastercard are the privatized court systems of the internet. If I end up on a random, self-hosted ecommerce site and decide to make a purchase - what guarantee do I have that the item will show up or be as-described? If I bought something through a bank transfer, reversing that purchase would be incredibly difficult. And, suing…
Or a 0.1% fee.