In the preface, Vonnegut states that as he reached his fiftieth birthday he felt a need to "clear his head of all the junk in there"—which includes the various subjects of his drawings, and the characters from his past novels and stories. To this end, he sprinkles plot descriptions for Trout's stories throughout the novel, illustrates the book with his own simple felt-tip pen drawings, and includes a number of characters from his other novels and short stories.
In many places in the book, Vonnegut provides simplistic descriptions of troubling themes in U.S. history. The result is passages explaining what things like racism, oppression and general inequality are without the contextual explanations that are often used to excuse these trends.
His drawings, intending to illustrate various aspects of life on Earth, are sometimes pertinent to the story line and sometimes tangential. They include renderings of an anus, flags, the date 1492, a beaver, a vulva, a flamingo, little girls' underpants, a torch, headstones, the yin-yang symbol, guns, trucks, cows and the hamburgers that are made from them, chickens and the Kentucky Fried Chicken that is made from them, an electric chair, the letters ETC, Christmas cards, a right hand that has a severed ring finger, the chemical structure of a plastic molecule, an apple, pi, zero, infinity, and the sunglasses the author himself wears as he enters the storyline.
In addition to Kilgore Trout, characters from other Vonnegut books which appear here include Eliot Rosewater and Rabo Karabekian. Rosewater was the main character in God Bless You, Mr. Rosewater (1965) and a minor character in Slaughterhouse-Five (1969), while Karabekian later became the main character in Bluebeard (1988). Hoover's secretary, Francine Pefko, previously appeared in Cat's Cradle (1963), where she performed secretarial duties at General Forge and Foundry, in Ilium, New York. (Pefko also appears in "Fubar," a story released posthumously in Look at the Birdie.) Vonnegut uses the name "Khashdrahr Miasma" for a minor character, in reference to a character in Player Piano. The vicious guard dog, Kazak, was Winston Niles Rumfoord's pet in The Sirens of Titan (1959) and Selena MacIntosh's guide dog in Galápagos (1985). Many of Midland City's inhabitants reappear in Deadeye Dick (1982), which locates the city in Ohio.
The title, taken from the well-known slogan for Wheaties breakfast cereal, crops up in a key scene late in the novel when a waitress, apparently ironically, says "Breakfast of Champions" each time she serves a customer a martini. Vonnegut, in his typical ironic manner, mocks the legal and copyright systems as he notes meticulously that Breakfast of Champions is a registered trademark of General Mills, Inc. for its breakfast cereal products, and that his use of the term is not "intended to disparage their fine products."
Vonnegut refers to himself as "Philboyd Studge" in the preface, a name which he claims his friend Knox Burger associated with cumbersome writing. The name appears to have been borrowed from a short story by Edwardian satirist Saki. ("Filboid Studge, the Story of the Mouse that Helped", describes the success of the eponymous breakfast food through bizarrely counter-intuitive advertising.)
The novel also describes a fictional extinct giant sea eagle called the Bermuda Ern. This allegorical species was later described in Vonnegut's book Timequake (1997) as a pelagic raptor, a "great blue bird", the looming extinction of whose population was being caused by its female members "kicking the eggs from the nest" prior to their hatching, rather than kicking the young fledglings from the nest at the appropriate time. In Breakfast of Champions their extinction is said to have been caused by a fungus, brought to the island by men (in the form of athlete's foot), which attacked the birds' eyes and brains.