Towing a separate hull is going to incur a severe drag penalty compared to carrying the same weight onboard, and it&#x27;s not going to be pulled along for free. It will reduce the ship&#x27;s speed and increase fuel consumption. There will be a direct tradeoff between weight carried in the form of the barge and weight the ship could carry internally for the same performance penalty.<p>Plus the barge will be traveling according to the cargo ship&#x27;s itinerary, not it&#x27;s captain or passenger&#x27;s preference, and at cargo ship speeds which are considerably slower than cruise ships. The slower speed means increased crew, food, drink servicing and entertainment costs compared to alternatives.