Wow CQ I'm sorry to hear what happened on your cruise. I'm surprised the bartender at the piano bar bugged you about disputing your drink bill. I disputed an error on Carnival Splendor (in 2010) and I didn't have this happen. I fear the headquarters have deceased the staff's budget and now the crew members are unhappy and showing it to the passengers like you. This should never happen.
I agree with you the crew for sure should have cleared everyone out of the show room after the 8:30PM comedy showing. That's not right and it causes the fighting among the selfish passengers who are refusing to leave. $12 per drink is highway robbery. Rudeness from the crew has no place on board.
My experiences on Carnival have all been good. But my last cruise on the line was in 2010, but I just booked a 15 day on Carnival for 2013 to Hawaiian so I hope things aren't like that on my cruise. It has 8 sea days they will be long days if I have to deal with that crap. I did notice that the longer cruises have older passengers so I'm thinking the Rap music won't be an issue on my cruise. Again I'm sorry your first Carnival experience was so bad.