Plus, there are sightseeing opportunities on land, and the neat thing about cruise ships is that they dock where the action is. Airports are always on the outskirts; ports tend to be situated pretty centrally in most cities.
Honestly, it's probably the nicest way to travel to faraway places, short of a private jet. It's not for everyone, but it's not a dystopian experience. The ships carry insane numbers of passengers, but they are also pretty darn spacious.