Executive Meddling: 2010 saw an unconditional ban instituted against so-called "cub porn" (underage anthro characters depicted in sexual activity); the admins said that the ban was not so much because of the content itself, but because FurAffinity's advertising sponsors were starting to cut funding off.
Not unique to furry art, FurAffinity, or art in general. There's always someone who will commission something then nitpick a detail and repeat until the artist gives up on them, and then post every individual sketch as 'art I commissioned from X', as well as people who copy the art and claims it as their own ('tracers'), or takes it wholesale and posts it without attribution ('assholes').
Commissioners who had been taken advantage of may fight back by either raising the prices of their art or making it much harder for other people to get a commission from them. The action screws over everyone else that would have been a normal paying customer.