It's simply provided freely in addition to any AAS bank.
So you can buy any AAS bank you want without having the synth it is made for. You install any AAS bank on your computer, it installs (or updates) the player in addition, do you have the synth or not... it doesn't matter. Therefore you'll be able to use all the AAS banks simply with the player without having the synth (of course without the ability to tune at your ease the patches included with these banks, but it allows you to use them "raw" in your compositions).
And the same copy of the player is compatible to any of these banks. No need to install several copies of the player.
All the AAS banks are so beautiful that even raw in the player they can have a great interest.
Conclusion: buy any bank from AAS... you get the player with it.