Norbert Leo Butz and Michelle Federer, who play Nate's parents, were both part of the original Broadway cast of Wicked, which is referenced several times throughout the film.
When Nate performs "On Broadway" in Times Square, a man comes up to him and tosses him "one thin dime", and compliments Nate on his performance. That man is George Benson, who had a hit with the song in 1978. George's version of "On Broadway" is also used in the opening scene.
The movie begins with the song "On Broadway". Bob Fosses semi-autobiographical movie "All That Jazz (1979) "also begins with this song, and one of the very first shots in "Better Nate Than Ever" is a poster showing Fosse's wife Gwen Verdon.