I was actually at Disneyland yesterday and kept thinking: "this place will be intense on 4 September."
I don't know that (for instance) the Lego store at Downtown Disneyland will be open at midnight. But I guarantee they will have stuff the very instant they open on the 4th.
And that's not to mention the actual Star Wars store they have right outside the Star Tours ride.
I do _not_ envy the people who have to work there those days...