I have never cruised but have taken many tours. I understand that on cruises, gratuities are added to the bill- I presume in the manner of incidentals charged to one's room at a hotel. I would strongly object to that practice as it defeats the purpose of a gratuity being a reward for service. On the tours I have taken, the tour company makes a suggestion as to the amount one can offer to a tour director, driver, or local guide. The actual amount is left to one's discretion. We have paid the suggested amount, we have paid more, and we have paid less- all where warranted. In my opinion, that is the way all gratuities should be handled.