They're cheap because they are full of misprints. I have cards from that and the cut is off by a lot. That being said, I do think they are only from set 4 if I can remember correctly (but the wiki indicates that the Fellowship block one was from the first 3 sets so I'm not 100% sure). They are good for two purposes: 1. You have almost no cards from set 4, or 2. You want to play a draft game. The draft packs have a set number of cards of certain types (eg. companions). They're basically miniature decks.
TLDR; you get what you pay for.