As others have stated, it was not banks, but credit card companies.
The street goes two ways: The credit card companies can choose who they want to do business with and if they choose to do business with the wrong company, they can get sued.
Currently, Visa and MasterCard are named in a lawsuit against PornHub because of PornHub’s actions.
As long as the credit card companies can be sued for doing business with the wrong companies, they have to be allowed discretion which companies they do business with.
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