The relationship between Wilson and Ed echoes the relationship between the literary characters of Don Quixote de la Mancha and Sancho Panza, as seen in many movies, such as Man of La Mancha (1972) and the classic Russian film Don Kikhot (1957).
During filming, Steven Soderbergh was unsure exactly which scenes from Poor Cow (1967) he wanted to use. So he asked Warner Bros. for permission to use the entire film so that he could choose the scenes later. But Warner Bros. refused. Soderbergh told the head of Warner Bros. that he would never make a film for him again. The executive relented and allowed Soderbergh to use any scenes from the film that he wished.