It would be interesting to know where the supplies come from -- do the American ship everything halfway across the world from the USA, or buy things from New Zealand?
both. (for mcmurdo/south pole) most of the dry/canned/frozen food is procured in the USA and loaded on a vessel in port hueneme for the once a year resupply vessel.
"freshies" are ordered from new zealand and flown down on available flights.