I wonder what kind of liability do third parties like a payment processor has regarding the content they are enabling. For me, the contract is between the compa

I wonder what kind of liability do third parties like a payment processor has regarding the content they are enabling. For me, the contract is between the company and payment processor. Why do MasterCard and visa exert their influence on third parties. Its not like I would go after visa if onlyfans was found enabling cp. I would go after onlyfans and demand they release details of creator of cp and then go after them but why involve visa ? Currently visa is acting as a gatekeeper, imposing their ideals on a third party doing business.