Suprised too...
I was suprised too when my wife signed my stepson (he's 9) up for a free email service & was bombarded by XXX sites. She has too check his mail before he can see it & I set the filters on high. As for the age thing, I believe these sites go out of their way to find the very young looking 18 y/o's. They are probably legal, even if they are offensive.
Certainly there is no hunting like the hunting of man. And those who have hunted armed men long enough and enjoyed it, care for nothing else." ---Hemingway