Most of the info/opportunities you cite have to be looked for/sought out - an activity at least some, apparently, do not engage in. And isn't "Several days before the end of the cruise" actually one or two? Would it not be more ethical/honest/transparent for Viking to clearly state their "tipping policy" during the booking process in such a way that the potential cruiser can not avoid knowing about it? What Viking does is no better than hotels, etc. with their "resort fees", "convenience fees", etc. that the customer learns about in "oh by the way" fashion.