Not sure about the other payment apps, but few financial services consider it a violation to use them to receive payments for services that "depict or appear to depict nudity", "depict [...] illegal drug use", "depict [...] hatred or discrimination of protected groups or individuals".

If PayPal is actually going to enforce this, it will obviously have to remove Netflix, Steam, any book store from their platform, since they run terribly afoul of most of the above.