I highly doubt you will have any wet landings on that itinerary. Even on the British Isles/Ireland/Scotland trip we landed on tiny islands with very small populations that seldom see cruise ships. The zodiacs can access small local docks so you do not need to wade through water to get to ashore. One stop on the puffin island we had to step off onto rocks but no water issues. I would not suggest buying boots for this trip I think you will be fine. This is in an area where many cruise ships operate cannot imagine a wet landing. Most places would have small docks no problem for the zodiacs. It is Antarctica and remote areas of the Arctic where you need the rubber boots.