Sen. Lindsey O. Graham (R-S.C.) may have poked a sleeping bear recently when he vowed to go to war to protect Chick-fil-A from a group of Notre Dame students and faculty who oppose a planned restaurant on campus. Graham’s comments were the latest chapter in the political jousting over the chicken chain’s conservative politics and religiosity.

But what many don’t know is that Chick-fil-A is far from atypical in fast food. Many chains have roots in two pillars of 20th-century conservatism: Christianity and free markets.

Maybe the best illustration of these roots came on Christmas Eve, 1987. Richard Snyder, then chief executive of his family’s chain In-N-Out Burger, heard its jingle on the radio. “In-N-Out: That’s what a hamburger’s all about!” Snyder, a born-again Christian, decided the song needed something more. Instead of temptingly describing the juiciness of a Double-Double burger or the smooth sweetness of a vanilla milkshake, Snyder decided to add a question: “Wouldn’t you like salvation in your life?”

This edit reflected the culture that gave birth to and nourished fast food. The quest for spiritual freedom and the search for the nearest drive-through may seem like two disparate experiences, but they have long intersected in the United States. Although companies such as In-N-Out and Chick-fil-A are increasingly identified with other national and global big brands rather than their founding families, the religious roots of fast food remain evident in their philanthropic and political activities as well as their packaging.

Many conservative Christian fast-food chains date to the postwar period. That was the moment when, in 1946, Southern Baptist businessman S. Truett Cathy launched what would become Chick-fil-A. Cathy was a Sunday school teacher who decided to close his restaurants on Sundays so his employees could go to church and spend time with their families. The decision also ensured that the chain reminded diners that obedience to the Christian Sabbath superseded the buying and selling of sandwiches. In the competitive world of fast food, forgoing a weekend day of profits shored up Chick-fil-A’s values-forward reputation.

Two years later, in 1948, In-N-Out debuted in Southern California. At the helm were Esther and Harry Snyder, who were raised in the Catholic and Methodist traditions.

Their son Rich, however, later discovered the evangelical Christianity that flourished on the West Coast alongside their burger business, and he inspired his mother to join him after his conversion in the 1980s. Rich and other members of his generation of In-N-Out heirs were and are prominent fixtures and supporters of the Calvary Chapel in Costa Mesa, one of the leaders of the Jesus Movement of the mid-1960s.