A subscription is supposed to offer accessibility to all that is a part of the game* (not "gimme" but opportunity). Having things exclusive to the TCG and Blizzard Store goes against that core concept. I believe that Blizzard either ought to have alternative means of obtaining them, or switch to the F2P model. As it currently stands, WoW has become something of an unfortunate hybrid.
*Just to be clear, I am fine with the exclusivity of things attached to Blizzcon and Collector's Edition.