mefordis, just can't understand how you could possibly spend $400.00 on a Thanksgiving meal for 15 . I had a 14# turkey with ALL the trimmings, casseroles, rolls, pies, drinks for $40.00 (turkey was on special with additional purchase and I bought on sale most items). It was to feed 12 people with lots left over. That is my budget for about 6 wks.!!!!!! And sometimes for two months!!!
I don't know the specifics, of course, and don't want to speak for mefordis, but I think it really depends upon what you serve, the ingredients, and how the meal is prepared. A few years back I bought an organic, heritage-breed turkey from a local farmer that clocked in at 16 lbs. and $65. Now, this was a delicious turkey and the purchase met my values in a few ways, so I don't regret it. Add in a couple bottles of wine, the sparkling cider for the kids, my special queso-dip appetizer (the ingredients for that one alone are about $13) and I can see how things get a bit higher than the rock-bottom amount one could pay.
We don't do this every year, of course, and had a particular reason for going full-on extravagant for that Thanksgiving. I could have "done" the meal for $40 or $60 or $whatever, but that wouldn't have met my need on that year.