Longtime fans of "South Park" will remember that Trey Parker and Matt Stone created the entire two-part episode "Cartoon Wars" in order to criticize "Family Guy's" style of humor, with Eric Cartman going out of his way to point out the differences between the two shows and discovering that the writers for "Family Guy" are a bunch of manatees.
These two episodes are filled with explicit jabs at the frequent cutaway gags in "Family Guy" –- something which the team from "The Simpsons" appear to hate just as much as Parker and Stone do. "After the first part aired, we got calls from people at 'The Simpsons,' saying 'thank you, thank you,'" admitted the duo during a DVD commentary of the episode. "Because they actually hate 'Family Guy' more than we do, even though they won't say it."
On top of that, the two showrunners also said they received thank you calls from people working on "King of the Hill" and claimed that "Family Guy" is resented across the industry for its style of comedy and writing. That said, considering that "Family Guy" and "The Simpsons" would later go on to have their own crossover episode in which they comedically rip each others' shows, one might assume they don't actually hate the series as much as Parker and Stone do. In any case, there's no doubt that "The Simpsons" will never be as vocal about this hatred as "South Park" is.
