I am 53 and have been around the cruising block for awhile (double entendre intended). There are still some people who like to live discreet lives, due to business and family issues. It is their choice and they should not be criticized for it.
We have only been on mainstream cruises, and were so thrilled to discover a "Friends of Dorothy" meeting onboard these cruises. We have met some of the most lovely people from all over at these meetings. "Discretion is the better part of valor". It is nice to get together with other people with the same interests and lifestyles. Just like it would be good to get together as doctors, or lawyers, or collegiate associations. You share things in common. It's nice to know other people on the cruise you can have pleasant conversation without the raised eyebrows due to who your partner is. Inclusion and camaraderie help life be less stressful and secluded.
When I was younger, we used "Friends of Dorothy" when checking people out in mainstream life. You could easily say, "I think he is a friend of Dorothy" to your friend out loud and only they would know what you were saying. Having codes is not a problem, Southern Belles certainly have a very developed one (read The Southern Belle Primer by Marilyn Swartz.) Having codes is a way of being polite in public without letting "all your business" be known.
No matter what the name is, I still believe that these meetings help you meet others who are liked minded and may lead to lifelong friendships. If you don't want to be social and go to the meetings, don't go! No one will be upset.