It's just a little photo album to share KLM pictures. The fact that a few people upload A.net photos with a little watermark of their own, is questionable, but you'll always have characters like that.
If it doesn't happen on Facebook, it'll happen of Flickr or any other website. Quite impossible to police the whole WWW. If photographers don't want it to happen, don't upload to the WWW without a watermark. In that case, A.net has a big leak: A FC member doesn't get to see a watermark and your photos are wide open for ripping.
It sucks, but it's just a fact of the modern times of internet.