Yes, it is $10 per person.
We are a family of four and have always gladly paid these tips (plus have given more).
These men and women do a remarkable job.
But most importantly, cruise lines (not just Carnival) uses gratuities as the way to pay these employees.
So these are not "tips" in the true sense of the word....this is their salary.
If people do not tip, these individuals do not get paid.
Personally, I wish Carnival would call them what they truly are....service surcharges and include them at the time of purchase like they did the fuel surcharges.