It's just like here you wanna be a member of renderosity you have to follow the workings of the site or be banned. Not exactly. PayPal is acting as a financial institution. They've structured their system so that, as a merchant, they can fine you if you fall into certain categories... Categories that they define and change without notice. In the case of digital arts, specifically, if you use PayPal as your payment gateway, and they decide that what you are selling is "adult" (a term which they leave undefined but which, as precedent has shown, has been applied arbitrarily), then you can and will be fined within their limits. This is why we aren't considering PayPal as a gateway at all. While many gateways restrict services based on moral conditions (most of which have clearly spelt out terms), none of them fine you for violation. Revocation of service providance is the only legal penalty for violating the terms of service, except in cases that may result in prosecution by the authorities of your locality. Luckily, we are all RTFTOS type A people, so we'll be avoiding PayPal, lest they decide to fine us for hosting pictures of naked Vicky. ;)