Blubelle I wouldn't argue with you, but I think your presuppostions about who the people on board are like are probably wrong.
There is no such thing as class, only income levels. DH and my BiL both have lower income backgrounds( their fathers were apostman and a factory worker) but if neither is a dresser up, both enjoy the finer things in life. I have to go back another generation, for my approved low income background.
But one of the things I have learnt is never to have preconceptions about people. I have talked opera, Egyptian archaeology and books, to name but a few, with the most unlikely people.
As I said, we are going on a short cruise, with our DD, just to sample life on a luxury cruise ship. We are unlikely to do anything longer as I am prone to seasickness.