The name "Captain Greybar" is an inside reference to the building where Chris' father, Bob Elliott, and his radio and stage partner Ray Goulding, had their "Bob and Ray" offices for many years (The well-known "Graybar Building" in NYC). Bob & Ray also had a company called GEG, which (long story short) had to be changed from Goulding-Elliott-Graybar to the differently spelled Goulding-Elliott-Greybar, under threat from the Graybar Building's lawyers. So, Chris gets the last laugh on those lawyers with the name of the tyrannical captain.
David Letterman appears as the "Old Salt in the Fishing Village", but the credits list him as "Earl Hofert". This is an inside joke for Letterman fans, as he also referred to himself as "Hofert" in some skits back at his old program Late Night with David Letterman (1982) on NBC. In real life, Hofert is an uncle of Letterman's on his mother's side.