Although most cruise lines are reporting high occupancy levels, it does not necessarily mean they are profitable, according to some chief executives of major cruise lines.

One cruise line president, who asked to remain anonymous, said that his ships, as well as others must be 90 percent to 95 percent full to maintain a successful image, and at the expense of larger profits, he and his competitors discount and offer free passage to achieve this "cruising-full image."

"Only 10 percent of the passengers on any given cruise are paying the full brochure rate, and the line must give 10 percent back to the travel agent," he said.