They need to hold something over the freeloaders heads to entice them. If they gave more warzones, how is this going to keep you as a subscriber? You won't, cause you'll be able to do everything you want for free, so why would you pay. You would join the rank of freeloader, and the game would sink even further.
Having something to do is the most important thing for any subscriber. Having a greater variety of stuff to do is also important.
The free respecs alone are a huge reason for me to stay subbed.. When I pvp I switch specs a ton. I want to tank.. I want to heal... I want to dps.. etc etc.