I have only been on ocean cruises but have been looking at a Viking river cruise in Europe. There seem to be many with a hotel stay of 2 days before you get on the boat and another 2 days off the boat at the end. These are stays in hotels and only breakfast is included. After ocean cruises, with ALL meals included, this strikes me odd to have to pay for more meals while on the cruise itinerary. Is this common among cruise lines?