The cruise lines are really sleeping on this market. People who can work remotely could cruise much more often if only the internet on the ships was more reliable. Some lines are doing better in this regard but more could always be done. They can't afford to give this segment of the market to Hawaii, Vegas, Sandals, etc...
I'm not sure I'd want to work on vacation even if I could (matter of fact I don't really like working at home, I like seeing different walls from time to time), but it's normal to a lot of people.