Apparently, Duck Soup was a popular title, as it appeared no less than three other different times between 1927 and 1944. Stan Laurel and Oliver Hardy featured in one Duck Soup (1927), while Chico and Harpo's lemonade peddler nemesis, Edgar Kennedy, starred in another Duck Soup in 1942. Their duel with Kennedy is very reminiscent of the types of standoffs Kennedy had with Laurel and Hardy in their comedies together. Daffy Duck and Porky Pig also piped in with Duck Soup to Nuts in 1944.

They say imitation is the highest form of praise, right? Well the Marx Brothers were smart enough comedians to know that their best comedy bits should be based on proven traditional gags. Case in point: the hilarious mirror sequence in Duck Soup was not an original piece of comic business. Leo McCarey adapted it from an old vaudeville routine. The gag sequence also showed up in an early picture called The Floorwalker (1916), but not before French comedian Max Linder used the gag in Seven Years Bad Luck (1921). While this gag was used many times on vaudeville, it was the first time the Marxes had performed the routine.

A long-time "Marxist," Woody Allen has paid homage to the Brothers Marx in many of his films. He makes a nod to Duck Soup in his 1986 film, Hannah and Her Sisters (1986).