Can of worms is right. Looks like I was wrong about who in the ship's crew gets part of the gratuities. I was relying on a quote where Princess said "behind the scenes" crew took part in it. Then I see they talk about specific parts of the crew, just those who have some relationship with cruisers. Hmmm---
In any event, I still feel that gratuities are expected as part of their income, and I gladly pay that. It would take something catastrophic to make me entertain the idea of removing crew appreciation from my bill.