When Fritzi reintroduces herself to Jill at the start of the movie and Jill fails to remember her, Fritzi reminds Jill that the previous summer, they had been in the play "'night, Mother" together. The joke is that "'night, Mother" only has two actors in it, and is an extremely intense, wrenching, emotional experience (it is about an adult daughter preparing her elderly mother for the fact that the daughter is going to commit suicide), so there is no way that Jill could have forgotten having already met Fritzi without Jill being incredibly self-absorbed.
In joke: Bert Hanley's character, a washed-up songwriter turned director at summer camp for theatrical kids, has the same name as the unseen business manager mentioned in 1962's Whatever Happened to Baby Jane, involving Bette Davis as a former child star.
The song Ellen listens to from her "Broadway ballads" mix CD, is the song "Imagining You" which is from the musical "Birds of Paradise". Writer and director, Todd Graff, starred in "Birds of Paradise" when it first premiered Off-Broadway.
During a 2016 interview with Terry Gross on the National Public Radio program "Fresh Air," Anna Kendrick said that when she performed "Ladies Who Lunch" for this movie at 16, she had never seen "Company," the musical from which it comes. But she had seen the song's original performer, Elaine Stritch, sing the song three years earlier when both Kendrick and Stritch had been performers in a Broadway revue at Carnegie Hall called "My Favorite Broadway: The Leading Ladies." About the experience of being in the same rehearsal and performance space as Broaadway legend Elaine Stritch at just 13 years old, Kendrick said, "she did walk around in just a man's shirt and tights, which, you know, was a dream come true to watch her in action actually doing that.....to have seen how unapologetic she was off stage as well, that was very inspirational for that moment in my - in my teen performance of that song. ....she kind of threw herself around and, you know, any room she entered she just announced what it was that she needed. I mean, we - you know, we were doing a performance. It wasn't like we were hanging out at dinner, and she just came in and was like, somebody get me some bread. But she was - I don't know - she just seemed like very comfortable with the fact that she was a living legend. I mean that in the absolute best way."
In a December 2016 New York Times essay that Anna Kendrick wrote about the experience of making Camp, she said that "people have either never heard of it, or they want to tell me that it changed their life, no matter how inappropriate the circumstances."
In her December 2016 New York Times essay about the making of Camp, Anna Kendrick said that at 16 she was anxious to downplay the implication that her character, Fritzi, was sexually attracted to her roommate (and eventual nemesis), Jill. "Today, I would be thrilled to play such a twisted little character. At the time, I just wanted to wear makeup and have my hair done, like the other girls in the cast....I still had to go back to high school once this was over, and I so badly wanted to be the hot girl in a movie, not the girl who washes the hot girl's underwear by hand."
During the month-long rehearsal period in Manhattan, the (nonunion) producers of Camp had to find affordable housing for their non-New Yorker actors, which lead to Anna Kendrick living in the pantry in an uptown apartment that was already shared by three students.