Then, why was Larry David not in Seinfeld?
Larry didn't consider himself an actor. Had Larry also been acting, he wouldn't have been able to watch everything that was going on the way he did. Also keep in mind, NBC wanted a Jerry Seinfeld show. They had no idea who Larry David was and they would probably never allow him to act in the show anyway.
Likewise, is George Costanza supposed to be Larry David? George appears in every episode except "The Pen" (third season). The character was originally based on Seinfeld co-creator Larry David but is surnamed after Jerry Seinfeld's real-life New York friend, Michael Costanza.
Consequently, are Seinfeld and Larry David friends?
Larry David and Jerry Seinfeld's enduring real-life friendship. Larry David, star of HBO's Curb Your Enthusiasm and Jerry Seinfeld have been friends for decades. “David — nearly broke — had given Leifer some jokes as a birthday 'gift.
Is Larry David the man in the cape?
At the beginning of “The Chinese Woman,” Jerry and Elaine spot Frank Costanza in the city with a mysterious man, wearing sunglasses and a cape, played by David. It's revealed later in the episode that the man in the cape is Frank's lawyer, who is helping him with his divorce from his wife, Estelle.