The automatic tips started after the cruise lines began letting people eat in the buffet area on the last night and morning. Used to be that you had to go to the dining room for those. It sickened me how many people would eat at the buffet ONLY for those meals, thinking that not being near their servers took the embarrassment out of not tipping them. Talk about tackY!
That said, I have changed my tips both up and down depending on service.