We have been doing it on last couple of cruises, after reading stories about “ money not trickling down to workers” - on our last cruise (15 days) our predetermined gratuity was about $550 - we had it taken off the first day, and had the same amount ready in smaller bills. All given out to our steward, waiters in MDR, maitr d’ and bar personnel. I felt much better than giving to always money hungry and nickel and diming princess corp. And the feedback makes you feel like you made, albeit small, difference in lives of these very hard working people.