I don't know of any tradition of gift-giving for Midwinter at American stations, but I have heard that there were formerly air drops at midwinter at McMurdo and South Pole stations. Those have been discontinued.
I suppose gift-giving would make more sense at smaller stations, but we have 153 people at McMurdo this year, and 43 at Pole - that's a lot of people to get gifts for.
However, as you say we had some exotic fare for dinner, people put on their best clothes, and most of the Kiwis from Scott Base came over for a visit, and afterwards those who wanted went and drank too much. All in all it was a good day.