"On Thanksgiving Day all over America, families sit…

“On Thanksgiving Day all over America, families sit down to dinner at the same moment — halftime” is a quip showing that televised football games are as much part of the Thanksgiving tradition as the turkey. The saying has been cited in print since at least 1984 and is of unknown authorship.

“Thanksgiving dinner eating takes 12 minutes, which coincides with halftime” is a similar saying from American humorist Erma Bombeck (1927-1996).

2 December 1984, Sacramento (CA) Bee, “Gaggle of Gab, Giggles Galore,” pg. 19:
THE OTHER 637 BEST THINGS ANYBODY EVER SAID Robert Byrne Atheneum; 256 pages $10.95
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There’s also some heavy leaning on Anon’s close relative Unknown, who noted: “On Thanksgiving Day all over America families sit down to dinner at the same moment—halftime.”

Google Books
The Silver Palate good times cookbook
By Julee Ross,; Sheila Lukins and Sarah Leah Chase
New York, NY: Workman Pub.
1985
Pg. 288:
“On Thanksgiving Day all over America, families sit down to dinner at the same moment— halftime.”—Anonymous

4 July 1986, The Times-Picayune (New Orleans, LA), “Good ol’ U S of A has lots to offer” by Angus Lind, pg. E-3, col. 1:
Where else on Thanksgiving Day do families sit down to dinner and bow their heads at precisely the same moment—halftime?

26 November 1987, Philadelphia (PA) Inquirer, “Saints march toward playoffs” by Bill Lyon, pg. 1-C, col. 1:
On Thanksgiving Day all over America, families sit down to dinner at the same exact moment—halftime.

Google Books
1,911 best things anybody ever said:
Many amusingly illuminated by antique etchings and line cuts
By Robert Byrne
New York, NY: Fawcett, Columbine
1988
Pg. 221:
On Thanksgiving Day all over America, families sit down to dinner at the same moment — halftime.
Unknown

23 November 1990, Frederick (MD) News, Celebrity Cipher, pg. F7, col. 5:
PREVIOUS SOLUTION: “On Thanksgiving Day all over America, families sit down to dinner at the same moment—half time.”—T. Urkey McDish.