Earlier, I found out that there is never an episode of Seinfeld where he complains about airline food or says "who are these people?" In fact, every single oft-quoted "stock Seinfeld quote" is actually from an SNL skit Jerry Seinfeld was in.
Like you watch this and it's kind of horrifying that he just goes through every single line that a 90s cartoon would recite when they do a standup comedy bit. "What's the deal with airline food!" "Why don't they build the entire plane out of the black box!" "The professor can build a phone out of a coconut but he can't fix a hole in a boat!" "Who ARE these PEOPLE?" I always assumed these all came from the Seinfeld standup comedy intros from the actual show, but no. He just goes down the list of every "Seinfeld joke". And as far as I can tell, these aren't riffs on jokes he would make a lot in his own shows or anything, this wasn't self-parody in the material itself, only the format.
As far as Berenstain situations go this one is pretty tame, because Jerry Seinfeld is the one saying all this shit in a skit about standup comedy. It's just interesting that the wires all got crossed on this.