The majority of submissions on FA are not in fact adult/mature marked!
But the majority of fav's and views go to mature works, not to mention the non-filtered works are usually still sexually charged. Like, for instance, fursonas/avatars that have godlike, or "enhanced" (more muscle, bigger bulge, 7" tall, long flowing hair/headfur/whatev, huge breasts) bodies, are shirtless (but still have on pants, don't use the "o i have fur u fail lolol" excuse), wear bondage gear to the store, so on
FA is indeed for the porn, but it's definitely more than that. It's grown into a sort of community that you don't see on, like VCL forums, FAP, Yiffit, so on