It would seem to me that cruisers have a choice of route they take. If they decide on passing through pirate infested waters, they do so at their own peril. Commercial ships usually have no such choice and that is why there is a difference. Just like cruisers can (and should) wait for a good weather window when attempting a passage.
It may not be "piracy" as such, but crime against cruisers is definitely on the increase. A cruiser was shot aboard his boat in Bequia last year, BEQUIA, for crying out loud!. Many boardings, break-ins and robberies in St. Vincent, St Lucia, Antigua and St. Maarten over the last year or so. Don't even think of sailing too close to Venezuela on your way to the ABC's or Trinidad.
Choice, what choice? Seriously, if one can't even sail to the traditionally friendly islands of the Eastern Caribbean without these hassles what are our choices? Would you suggest we all stay home and follow other people through their blogs and forum postings. Oh wait, if we all stay home, who will blog or post of adventures in far away places?
Adventuring comes with risks, be it from weather, rocks or "piracy". People die climbing Everest every year; should nobody climb Everest?
One should not stop living for fear of dying.