Underwater sites are particularly harder to protect from looters than above / underground sites. If the stakes are high enough, scuba diving is a reasonable option for the criminally minded.
It wasn’t long before Costa Concordia was looted for its treasures.
> It wasn’t long before Costa Concordia was looted for its treasures.
What treasures were there, panties of Francesco's Moldavian lover?
Passengers possessions - e.g. jewelry, watches. Technical equipment on the ship. Items from the on-ship shops. Interesting artefacts (ships bells are often a prized loot from wrecks).