500 freebies would make a noticeable bump in most crowds but not really this one, the place was packed! I don't think the track was prepared for that big of a crowd; concession lines were really long and they ran out of a lot of items.
On a side note, having the main concession stands situated so the lines run right in front of the main grandstand tunnel is a really bad idea. I know it's been that way forever but it doesn't help, even on a "normal" attendance night.