“A refrigerator is a place to store leftovers until they are old enough to throw out”
“A refrigerator is a place where you store leftovers until they are ready to be thrown out” is an old comic observation.
A newspaper comic caption on September 8, 1954 was: “Our refrigerator is full of stuff that’s too old to eat and not old enough to throw out.” Two years later, on September 24, 1956, the full leftover joke appeared: “A refrigerator is a place to store leftovers until they are old enough to throw out.”
“Cooking tip: Wrap turkey leftovers in aluminum foil and throw them out” and “I just wanna be rich enough to throw leftovers away after dinner instead of putting them in Tupperware and throwing them away a week later” are related sayings about leftovers.
8 September 1954, Bridgeport (CT) Telegram, ‘The Neighbors” cartoon by George Clark, pg. 5, col. 3:
“Our refrigerator is full of stuff that’s too old to eat and not old enough to throw out.”
24 September 1956, Indiana (PA) Evening Gazette, pg. 1 (masthead):
A refrigerator is a place to store leftovers until they are old enough to throw out.
Google News Archive
4 October 1956, Warsaw (IN) Times-Union “Little Liz” cartoon caption, pg. 5, col. 2:
A refrigerator is a place to store leftovers until they are old enough to throw out.
Google Books
The New Speaker’s Treasury of wit and Wisdom
By Herbert V. Prochnow
New York, NY: Harper
1958
Pg. 119:
A refrigerator is a place where you store leftovers until they are old enough to throw out. Ogden, Utah, Standard-Examiner
Google Books
20,000 Quips & Quotes
By Evan Esar
New York, NY: Barnes & Noble Books
1995, ©1968
Pg. 318:
A refrigerator is a place where you store leftovers until they are ready to be thrown out.