I know lots of people use Tip Envelopes for MouseKeeping, restaurants, and other things around WDW. Are they something that would be useful on cruises or not? I make things on the DISigns board, and someone asked if I made tip envelopes for cruises, and I do not have any. Before I would take the time to make any, I am wondering if they are even a thing, or would be something people used before I expend the energy. I don't do the Disney cruise thing, so I am woefully ignorant in all things cruising. TIA for any answers.