When I was on the Breeze, I interviewed Buth Begovitch... one of his duties was implementing the George Lopez Punchlines brunch.
Butch Begovitch - A Rising Star at Carnival
I did not talk to him about breakfast on sea days (because I didn't even think about it to tell you the truth). But he did say the purpose of the "brunch" was really about spreading out passengers; easing the demand in Lido buffet, Guy Fieri's and the C side bar-b-q.
He did say it's actually a tough gig for the comedians, trying to do a 10 minute act, while people are shuffling around and eating.
But... he did say they were averaging 1000 people per day, on the sea days, for the brunch. To them, that was very successful.