I don't think the reasoning here is related to money, for once. As I understand it MREs are actually fairly expensive to procure through the logistics system ev

I don't think the reasoning here is related to money, for once. As I understand it MREs are actually fairly expensive to procure through the logistics system even in CONUS (something on the order of $10 each). The MSNBC article that is linked mentions the cause as being simply that the soldiers and Marines pulling security have to be the last ones there, so they need to start moving the support staff (including cooks) out earlier. They're probably already almost maxing-out the airlift and sealift they're able to provide to take servicemembers and materiel back out of Afghanistan, which would give a plausible reason for why the cooks have to start leaving half a year in advance of the rest.