There is reference to a company, "Cardiff Giant". The Cardiff Giant was a hoax conceived by George Hull, a confirmed atheist, after having an argument with a fundamentalist minister about the existence of "Giants in the Earth" as referenced in the book of Genesis. In 1868 he built a 10 foot carved statue, treated to look ancient and buried it. A year later, when workers were hired to dig a well on his property in Cardiff, NY the statue was discovered. A great public discussion ensued as Christian Fundamentalists defended the statue as proof of the giants. The debate went on long enough for Hull to make over $20,000 - charging 50 cents to peek at the "historic artifact".
Jon's grandmother Joan Favreau cameos as a field trip guide in a scene in Central Park Zoo. In another reference to Swingers (1996), Vaughn's character Ricky asks Favreau's Bobby if he could pick up the "vibes" a girl was sending him.
Vince Vaughn's character makes derogatory comments about the film Mickey Blue Eyes (1999) while on their flight to New York. That movie (also a mob comedy) featured Vincent Pastore, the actor playing their driver in New York.
When Bobby goes to pick up Chloe, she is watching a news story on fires. Ricky started this fire at the beginning of the movie when he threw is matchbook out the window. There is a reference to Ricky (Vince Vaughn) shoving a shiv (knife) into someone's neck. This is a reference to his part in _Psycho_.