Another plausible arrangement is to have a Shopping Boss "in between" the Boss and the Mealbosses. Besides making sure there's somebody who understands the menu helping with the shopping, the Shopping Boss can stand in at food delivery/sort, and if any Mealboss becomes unable to perform their duty, dinnertime.
The Shopping Boss role can also grow into "Food Coordinator" - responsible for overseeing the post-shopping sort (see below), keeping the materials and ingredients segregated by meal, general oversight of food storage (including leftovers) and food preparation areas (including policing cleanup). In particular, somebody needs to be responsible for draining and re-icing coolers every day.
Arrangements for payment for shopping must be worked out between the Boss and Finance Minister. One easy strategy is for the Boss (or shopper) to charge everything on an unused personal credit card, then present receipts and collect all at once from the Finance Minister.
Remember - we're camping; there's a LOT of food involved, and we need to be sure food is stored and handled in a safe manner. Refrigeration (or lack thereof) is a primary concern of the Boss or designated Shopping Boss.
However, bottled water is as expensive as pop, and we are searching for alternatives that should be just as good, but much cheaper. One suggestion is to issue a GPNDG/WetLeather plastic sipper bottle at Registration, and tell people to use only this container for drinking water, to be filled from large central "Culligan" type jugs.
Reference: 2001 Shopping List, annotated
Reference: 2002 Shopping List, annotated