You are far from alone. We cruise for the itinerary and when a cruise makes sense due to distances, logistics, availability and qualify of tourism amenities, etc. Alaska, a Tahiti cruise that included the Marquesas, a repositioning transatlantic, a Panama Canal passage, Easter Island, Antarctica are examples that come to mind.
There are also sites where a cruise offers a better degree of security in unstable regions. A tourist who wanted to see the Great Pyramids of Egypt, for example, would better off taking a cruise instead of attempting a land-based visit.
Otherwise, cruising does not have that much to offer and ship board life is often tedious.