Casa Bonita, the family fun restaurant Cartman committed fraud for an opportunity to get in, is an actual restaurant in Denver, Colorado. Matt Stone and Trey Parker have visited there many times and a menu for the restaurant is framed in their studios. In 2021 Parker and Stone purchased the restaurant and are now the owners of Casa Bonita. A statue of Cartman enjoying sopaipillas where guests can their photos taken and a costumed character of ManBearPig were added to the restaurant following Stone's and Parker's purchase.
In a previous episode, Butters was frustrated to realize that all his evil plans had previously been done on The Simpsons. Perhaps deliberately, Cartman's plan to keep Butters away from Casa Bonita (claiming a comet is heading straight for South Park) is also an idea from a Simpsons episode (Bart's Comet).