Every forum needs porn... But the options available to porn permitting sites are much more limited than to non-porn permitting sites.
I have a site for sex tourism using this forum software. The line between porn and non-porn is blurry. But if you get categorized as a porn site, you can't accept paypal or many other forums of money transfers.
In the real world, degenerate gamblers and perverts are close cousins. In the hypocritical world of marketing, staying focused on your market is critical.