“You don’t win friends with salad!” is what Homer Simpson and family danced in a conga line before vegetarian daughter Lisa on the animated television show The Simpsons (“Lisa the Vegetarian,” air date October 15, 1995). The saying is often worded a little differently—“You can’t/don’t win/make friends with salad!”
 
Salad has long been served at friendly gatherings—despite what Homer Simpson says.
 

Wikipedia: Lisa the Vegetarian
“Lisa the Vegetarian” is the fifth episode of The Simpsons’ seventh season. It originally aired on the Fox network in the United States on October 15, 1995. In the episode, Lisa decides to stop eating meat after bonding with a lamb at a petting zoo. Her schoolmates and family members ridicule her for her beliefs, but with the help of Apu, Paul McCartney, and Linda McCartney, she commits to vegetarianism.
(...)
Homer and Bart continue to give Lisa a hard time at home, particularly since Homer is ready to host a barbecue, complete with roast pig. Bart and Homer even form a conga line and sing, “You don’t win friends with salad!”
 
YouTube
you dont win friends with salad
Uploaded by MrShadowfactory on Apr 10, 2010
 
11 September 1991, Mobile (AL) Register, “Save the environment—and eat better” by Barbara Gibbons, pg. 16A, col. 3:
Cut a milk carton in half, fill with potting soil and let the little ones grow some leaf lettuce in the window—an opportunity to make friends with salad!
 
You Don’t Make Friends with Salad
If You’re Not Laughing, Then You Must Have Above-Average Intelligence
(First blog post is from 2005—ed.)
 
7 August 2005, Brandon (Manitoba) Sun, “Nutritionists toss salad myths” by Sadia Latifi, pg. 2, col. 1:
“You don’t win friends with salad! You don’t win friends with salad!”
—Homer Simpson and family, singing
You just can’t go wrong with a salad, as opposed to what the carnivorous Simpson family—minus the vegetarian Lisa—had to say in that well-known episode that featured a flying “Whopper for the copper” and a soaring dead pig.
 
New York (NY) Times
Beyond square meals: America’s food revolution
By A.O. Scott
September 29, 2006
The United States of Arugula. How We Became a Gourmet Nation. By David Kamp. Illustrated. 392 pages. $26. Broadway Books.
(...)
(The cover depicts Lady Liberty clutching a bunch of greens in place of her torch, proving that Kamp’s publishers have turned a deaf ear to the wisdom of a leading American gourmand, Homer Simpson, who once observed that you don’t win friends with salad.)
   
OCLC WorldCat record
Enemy of the steak : vegetarian recipes to win friends and influence meat-eaters
Author: Nikki Goldbeck; David Goldbeck
Publisher: Garden City Park, NY : Square One Publishers, ©2007.
Edition/Format:  Book : English
 
Google Books
Consider the Oyster:
A Shucker’s Field Guide
By Patrick McMurray
New York. NY: Thomas Dunne Books
2007
Pg. 55:
Where else can vou find such an oyster-friendly slogan: “You don’t win friends with salad!”