To be clear - I've never cruised with HAL before, so I cannot comment on what is included in the cabin. The reason I bring a corksrew, is because years ago, we bought one in teh gift shop of Royal Carribean. We had a wine bottle gifted to us from our travel agent, but no way to open it, so DH picked up a small souvenir corkscrew. It lives in our suitcase, so we always have it with us when travel.
ETA: These days, even good wines have screw tops, and you no longer "need" a corkscrew. I wonder if the corkage fee still applies?