In an obvious reference to the recently departed Pernell Roberts, after Ben, Hoss and Joe discuss bringing more "Culture" to the Virginia City anniversary party, possibly Shakespeare, as Hoss and Joe are departing Hoss intones "To Be Or Not To Be" at which point Michael Landon (whose relationship with Roberts was never the best) says "Nah, we got rid of him!"
Among other reasons Pernell Roberts left Bonanza was his desire to get back to legitimate theater. That was the inside joke.