This is consistent with my recent experience on two different Oasis class RCL ships (Allure and Wonder). It's kind of hard to circulate to people that anyone is interested in a game. People will walk by, see the empty table and just go to a different game or leave the casino altogether.
Literally the best strategy I've found is to just sit down at the table to signal to anyone walking by that there's action. If you do this on Day 1, you're more likely to get action throughout the week.
Sometimes you can get the floor to make a call for interested poker players, but they won't always do it unless you already have 5 players ready.
The rake is pretty egregious and becomes punishing if you don't get a decent amount of people reloading or joining the table.
Note: I was on Wonder in Europe and the action was great the whole time. Western Med cruises have people joining/leaving mid-week (Barcelona/Rome), so you don't have the full ship turn over every week.
