That's different. When I did it a few years back, we were allowed to take as much food/hydration/pogey bait shit as we wanted... sometimes to the detriment of the participant (there were some folks who had packed out far more food than they consumed).
There was, however, as simply (yet thorough) initial inspection of the packs for a few simple things:
a) Do you have six bricks?
b) Are all electronics turned off and put away? (e.g., watches and cell phones could be packed away, but not used during the event. No GPS units at all)
c) No other prohibited items (I don't recall the list, but it was pretty self-explanatory).