The short cruises, 3&4 nights over a weekend tend to attract large extended family groups that can be oblivious to their surroundings. Shorter cruises attract the younger demographic who don’t earn much vacation time. Other parts of the world get much more vacation time than in the US so go 7 days or less. The same demographic might prevail on some European lines, but I suspect not on P&O and Cunard short cruises. We were on a 4 day cruise on Cunard QE and found very few non-Brits aboard, and not only did they not party, the liked to dress up every night, not just the formal night. EM