When Quackser releases the horses at the end of the film, the words "VOTE NO" are visible in chalk on a brick wall. This is in reference to the Fourth Amendment of the Constitution Bill 1968, a referendum to change the Irish voting system.
David Kelly and Gene Wilder have starred in a version of Roald Dahl's Willy Wonka or Charlie and the Chocolate Factory. Wilder appeared as Willy Wonka in Willy Wonka & the Chocolate Factory (1971), and David Kelly as Grandpa Joe in Charlie and the Chocolate Factory (2005).