That's why I make sure to post photos that I don't really care if they get used by others without my knowledge. Most are of stuff that's not very nice anyway, horrible pen sketches and dozens of my face. My face spams my instagram account. Sounds like from the response that they're still selling users' works without telling the user. Their response is there to make it seem like they're doing something when they're doing nothing at all, however I really don't care personally myself.
So if others agree that they're just making it seem like they're doing something, when it's nothing, and want to change it, go! Write to them and tell them further it's not okay, etc. Just, I'm not helping you.