All drinks on board include a "hidden" 15% gratuity per our travel agent who cruises almost exclusively with HAL. It wouldn't look good to show a gratuity if the cruise line has a no gratuity required policy. This includes wine packages and all bar drinks. And, I understand this 15% is shared among all the crew members on the ship. Any additional gratuity you leave a particular person is theirs to keep.
If this is not correct, perhaps a representative from HAL could set us straight.
Congratulations for your 20 years of cruising with HAl. We reach our 100 day mark (3 years) our next cruise in October.