The main problem not being our inability to handle adult material so much as how it effects the Google ads.
Last I remember Scragg talking about it he couldn't separate what kind of ads different parts of the site received, so even if we were to make an adult section they'd still have the same problem of needing to moderate for the things they moderate now.
It's not entirely about what people can and cannot handle in terms of adult content, at least not when it comes to pictures.
As someone who has dealt with Google Ads (only made $100 every year for awhile), I can safely say it's not a matter of content, but of people who have nothing better to do than get others in trouble.
My sites didn't have the large amount of visitors as this site does, so naturally with more people comes a greater chance of those people who make Ned Flanders seem cool.