Pebble Beach Concours - Parking Pass

[avale]

I had a great time at the Pebble Beach Concours this weekend but the "free parking with shuttle service" was very frustrating as it was poorly marked and the traffic control people didn't seem to know what was going on. When I picked up my tickets at will call I asked the person how you can get parking passes for the numbered parking lots and she said you can't buy them. Does anyone know how one gets a parking pass for the number lots?

Thanks in advance!
Alan