Of course the first time cruisers are the optimal target ( for probably all the cruise lines). In July 12, when I interviewed Bob Dickinson, he said "we have the repeaters already, we need to get the first timers". And yes, for the mass market lines the family has become the big target.
However, that was before the rash of incidents, and the very negative media coverage. As I said, in time that mark will heal.
But, for now, the non cruising public still has a very negative view of cruising in general, and carnival in particular. Carnival is attempting to combat that by making their cruises so cheap people will overlook those negatives.
And that's why if these changes add to the negative perception, they could adversely affect those repeaters who understand those incidents were anecdotal, and cruising is perfectly safe.
For now they do very much need the repeaters... And it's not just Carnival in this position. Just them more than others in the current market.