Correct. We're having a fun time here.
Great idea! I second this.
It is. A tagline in a vintage TV commercial is obscure. As opposed to in-game references about Mario, Luigi, Bowser, Yoshi, the world they exist in, etc. Not going to argue this point.
It would be a good idea to keep "Haiku Hints" pertinent to the original source material of the game, rather than drawing references from outside sources such as vintage commercials, catalogs etc.