I personally think you asked an interesting question. How can the vendor sell something as copyrighted if they just copied another copyrighted piece of work......especially when they copy it word for word. I have bought a few of the question packs from these vendors and found they helped me a lot.
But now I am going to ask a really dumb question, and if it has been answered before I apologise, but I am a little fuzzy on this. If this site has such strict rules on posting copyrighted material (which is a good thing), how come we can post unisa material. Is it also not copyrighted??
I remember reading somewhere on this site at the time I raised the issue of notes belonging to UNISA freely available on this site that UNISA seems to turn a blind eye.
So, break the 'law' is ok as long as nobody is looking!