George Lucas has stated that the two main characters, Roger and Penny Henderson, are actually the parents of Richard Dreyfuss' character from American Graffiti (1973); making this film a bit of a semi-prequel.
While prominently billed, George Burns is only in the film for a little over a minute. He also only had three scripted lines. The rest of his dialogue came from a previous performance in "An Evening With George Burns".
Rosemary Clooney's final feature film appearance.
The musician who does all the music for WKB is based on Spike Jones, including his trademark checkered suit. The film's credits thank the Estate of Spike Jones.