Youâ€™ve probably noticed that the Detroit Lions and the Dallas Cowboys are Thanksgiving Day fixtures on the order of turkey and cranberry sauce. The Lions have taken the field every Thanksgiving Day since 1934, and the Cowboys have been suiting up on Turkey Day every year (except two) since 1966. How, you may wonder, did these traditions start? Are they the stuff of NFL folklore? Was Jim Thorpe or Curly Lambeau involved? Were there raccoon coats, straw boaters, and stogies? No, not really.