Besides, it's a well known axiom that Captains hate the social aspects of their job and would just as soon you left them alone anyway.
Any master of a cruise ship who dislikes the social aspects of the job is imminently employable elsewhere -- for example, as the master of a container ship or other merchantman. Thus, your suggestion that captains of cruise ships don't like their work is absurd on its face.
I'm sure that you're correct that once upon a time sombody wrote on a piece of foolscap somewhere that you're not allowed to say no to the Captain.
You would find this in any book on etiquette that addresses the subject.