I totally agree with Bob (green_rd)...offer an attractive fare to solo cruisers. I usually cruise with friends and family but would definitely cruise more often alone if the single fares were reasonable. I don't want to stay in an interior stateroom to be able to afford the single supplement. I enjoy a balcony but the double bump makes this choice unattainable for me, therefore, I cruise less often than I would.
So...would the cruise lines prefer I sail once a year or sail twice a year. If I cruised twice a year, the cruise lines would profit from the additional monies spent on that 2nd cruise for gambling, alcohol, souvenirs, shore excursions, etc. I think Carnival needs to come up with a viable solution to this problem such as the Norwegian Epic did or they will lose a lot of solo customers to the cruise lines that do provide attractive pricing for solo cruisers. Carnival does not need to spend money to re-vamp their staterooms or build "single" staterooms on their new ships, all they need to do is create single friendly rates. I could live with a single supplement if it wasn't the entire price for that invisible person sharing your stateroom. I know fares are based on double occupany but that invisible person does not add to your bottom line. Carnival offers a price differential for that 3rd or 4th person in your stateroom. The 3rd or 4th person is usually a child who has no authority to purchase ancillary products on the ship or on shore. Why not offer the same differential to solo cruisers, they would more than make up the difference in onboard spending. Also, once you attain Platinum status with Carnival perhaps there is an opportunity there to offer solo cruisers an incentive to sail with them.