Heidi became a part of sports and pop culture lore as NBC's decision to pull away from coverage of an American Football League (AFL) game between the New York Jets and the Oakland Raiders to air the film at its scheduled time of 7 p.m. Eastern, caused viewers to miss a frantic late comeback by the Raiders to win the game, prompting controversy and viewer complaints.

As Sesemann's niece, Heidi becomes cousin rather than simply companion to Klara, who early in the film is negatively portrayed as a hateful and spoiled child.

The film also added a subplot in which Heidi's grandfather, a church organist in this version, has long been unable to play because of a family tragedy, which is shown to be his daughter's marriage to Sesemann's brother and her subsequent death.

In the film, Fräulein Rottenmeier and Herr Sesemann visit the girls, and Grandfather deliberately leaves Klara alone on the mountains, knowing that she actually can walk but has been afraid to try.

NBC's network management had taken the decision to show the entire game until its completion even though it was contractually obligated to begin the broadcast of Heidi on the East Coast at 7:00 p.m.

Shortly afterward, Oakland scored two touchdowns within the final minute, winning the game 43–32 in a major upset.