Well, I've been paying for wow since the start of the game, and a few weeks ago was the first time I actually stopped paying, in my first ticket that wasn't even related to gametime they offerd me 3 days free game time to see if I like it again, when I said no I don't need it they told me to ask them for gametime whenever I would like to check back in... I guess if you've been a good customer you do get some gametime ^^
Friend of mine got 1 month free when he asked for it, so yes.. you do get gametime.
just don't be a moron when asking for it.