If free dining comes out, your AAA agent can apply the cheapest discount for you (you'd have to choose between the room discount and the free dining, no "double stacking"). The only problem with booking through AAA is that the agents don't work all the time; mine can't be reached at 7am on a Saturday, for example, so if a new, better discount becomes available, I don't have control to make that call myself at the earliest possible time. This might mean that I miss an opportunity at my first choice resort. But it can be done through them, you would not be excluded.
(This is only true if your AAA agent (A) has a clue and (B) cares about his/her customers. Sadly all to often on here we read that the AAA agent didn't try or wont' try)