I noticed when selling my casings that whole fobs were getting stupid bids, obviously because folk thought they would have an extra working fob. I always put in the description for my casings that the innards are worthless without a barcode as you cannot pair them to you car.
Now in saying that I am sure I have seen someone somewhere stating they can pair the newer fobs without barcode, I just cannot remember where?!
*edit* that seems to be for 2 fobs, so at £9 each so far they could still just be being treated as replacment casings as mine were going for that prices there, thereabouts