Doesn't have to be free, but the pricing model for WFA+AA wound up giving us one expansion pack's worth of content for the price of the full retail game originally (or more, depending on what region you were in). AA being 40 eur was in particular a slap in the face for people there.
Which really isn't any different to anything other companies do.
Look at blizzard and D3/SC2 expansion model. You get new content, pay like for full game and have millions of people jerking off how awesome and generous Blizzard is. Or how many Terraria reskins have you seen, next being more expensive then previous.
Other studio does the same and the hurt of butts will be felt 3 generations into the future.
Players double standards are simply stunning at times. Especially since you can make completely separate, full game out of WFA+AA.
I'm not being for or against that model here, I'm simply saying that everyone does that and I see no reason to bash only a single game for it since whole gaming market does it and since players are buying it instead of sharpening pitchforks, lighting torches and marching against evil gaming companies, I see no reason to get worked up against it.