Ghostbusters Reboot: 29 Easter Eggs, References & In-Jokes
3. Baba Booey!
Right at the end of the movie when the Ghostbusters have done their thing, the ghostly activity that the mayor's office continues to denounce as a hoax are discussed on a televised news report.
Strangely, the report is interrupted when a random guy in the background shouts "baba booey" and runs off (calling back to an infamous episode of The Howard Stern Show).
The reference is a strange homage to the moment in the first Ghostbusters movie when a televised news report was photobombed by a random New Yorker who stood creepily in the background.