Rav Moshe Z’l permitted someone to join a Thanksgiving “celebration” and eat turkey since in his opinion it is a national, not religious holiday (he uses the term, it is not found in their religious books). Rav Gifter I believe agreed. Rav Hutner Z’l was very much against celebrating thanksgiving.
In our family, if we manage to qualify for the shoprite promo for “free” turkey, we get one and save it for an off shabbos when everyone is home. It is usually shabbos chanuka.