I disagree that the mining claims are worthless. I actually like them way better as a prize than any type of "boost" that were droping from previous boxes. Now I can go to the asteroid every other day and get 10000 dilithium in a couple of minutes from just one mining site. Awesome stuff for all the characters I didn't get a chance to play much recently.
I agree though that these items should be account bound, not bound to character. I can understand the decission of keeping them out of the exchange, but I honestly see no reason why we can't put them to our account bank at the very least.
Personally I don't have this problem of hundreds of claims on a single toon, as I've opened several boxes on all of my characters, but I support the idea of making these claims account bound.