Per my AAA book:
You get:
Diamond Savings card with Discounts at various Stores/Rest. And Tours
free theme park parking
Lanyard, pin and luggage tag
Attraction Photo 5x7
Sov. Tix with 1 Magic morning entry with 3 day or more purchase
Disney character call If booked online
Now if you book thru Disney :
You will get:
A different Luggage tag, Lanyard, and pin
1 entry into magic morning with 3 day or more tix
Attraction Photo 5x7
Character call
I personally walked to DL from my hotel so never even saw parking area.
The discounts were worthless to me but Every family is different.