The way I see it, If I just wanted to sit and scratch my balls, a ship would be the perfect choice.
Instead I hike through the mountains, wander all around places like Yellowstone, Rocky mountain National Park, Grand Canyon,
This year I will stomp through the everglades, see Cape Canveral (and learn how to spell it) Stop at many beaches along the coast.. While camping I have skydived, snorkled, gone on whale watching excursions (Im sure you can find these on the decks of a ship too) Naturally, I can always slip behind a bush or something should my balls need scratching, so, some things never change.
Now, I could do all of that or I could sit in a bathtub looking at water for a week.
But like I said, Im sure the day will come that I just dont have the energy to do anything, and a cruise might be nice.