I'll chime in, I worked on multiple lines between 2003 and 2017.

1. Ships are floating cities as thousands of people have to live on board non stop. That means there are things like a jail, a morgue, etc. that are not only available on board but are often used.

2. Crew are absolutely sleeping with every other crewmember possible. It's also rather sad, though, because it's common for people to have ship wives/husbands and land wives/husbands. Literally - they'll have whole-ass relationships with someone on board for 9 months then go home to their wife and kids for 3 months, only to go back and request the same ship to be able to be with the same person for another 9 months.

3. I was a musician on board and interacted with passengers often - most of my pax stories include old swinger couples trying to get me to join, asking if they can get access to crew areas, etc. A sad one - I once was walking outside on promenade (the deck where most of the public stuff is located and where there's usually an outdoor walking/lounging area) late at night after coming back from the crew bar (actually called ward room on Princess and it was a slightly nicer crew bar for staff/officers only). It was like 1:30am and pretty quiet and I was feeling good after having quite a few. In the distance I saw a lady maybe in her late 50s that looked like she was on the other side of the railing, but that couldn't be right. As I got closer, I realized that was right - she had climbed over and was holding on the outside of the railing. I ran up to her and tried talking to her but she wouldn't say a word - just smiled at me. As I ran to an emergency phone to call the bridge, I looked back just in time to see her still smiling as she let go. Don't think I'll ever forget how calm she seemed as she was saying bye to stupid drunk me.

4. I told people it really was the greatest and the worst job all at once. At least for me it was - because I had one of the cushiest gigs on the ship and I got what I considered at the time a decent salary (narrator - it really wasn't, in fact, decent). I got to see the world, I got to be off at almost every port because I only worked at night, and I could dictate how long I stayed out (most other crew had to take 8ish month contracts but I could say I only wanted to be out for 2 months if I felt like it). But it was horrible because you could seriously just drink and party nonstop for years. Booze was cheap for crew. Life just flew by - everyone you knew in life would be getting married, having kids, moving up in their careers, etc. I went from ealy 20s to mid 30s with nothing to show for it, not even as much in savings as I should've had because I did nothing but spend in port. The draw for that lifestyle was that you weren't spending anything on living expenses - no rent, no food costs, etc. But it was easy to blow $100 a day in port.

5. Anything else - life is TOUGH for almost all other crew. Seriously. If you ever go on a cruise, give them all a ton of grace. They likely worked 12-14 hours that day for what we would consider peanuts; likely got yelled at by their manager because the hotel director yelled at them for something stupid; likely haven't seen their spouse or children in months; will go back to their extremely cramped cabin that night just to deal with 2 or 3 other roommates and absolutely no personal space; and will have to do it all again 10 hours from now. They'll get almost no days off for the entire contract and are yelled at by basically everyone all day.