Redolent of "Seinfeld":
Wondering how Jeff could sit on a plane for 5 hours without anything to read was taken from the season 9 opener (can't remember the title) where Elaine got mad at Puddy because he could sit in his seat with nothing to read and look blankly at the back of the seat in front of him. Season 9 was post-Larry so this theft was a case of larceny!
Larry's obsession with what David Scwimmer discussed with the stewardess was very similar to George's obsession over whether the actor playing him stole the box of raisins in "The Pilot".
Giving tickets to hotel staff also reminded me of Elaine giving tickets to "Rochelle Rochelle" to the Korean manicurists.
IMO, the high point of the show was the opening number from "The Producers", a play I haven't seen. Turning the production of "the Producers" into "the Producers" was clever but not funny, IMO. The idea that Mel Brooks would be tired of milking that particular golden goose is too far-fetched.