macmom111, TimC has every right to "adjust" tips if he felt the wait staff was not up to par. Timc is a frequent cruiser and knows what he should expect from the wait staff. Tips are tips and they are meant to reward good service not as a mandatory offering to supplement the crew's pay.
I have never had to adjust my tips due to poor service, although I did come close on one cruise. But I talked with the Maitre'd and the issue was promptly resolved, so no need.
As far as the OP's post goes, what is wrong with country music? You didn't mention which ship you were on, but Carnival does accommodate its customer's very well. If you were on the Holiday or the Conquest, you can bet that a vast majority of the guests on those cruises are country music fans because of where they sail from. You could also have been on a country music cruise! They have those too.
I have always found the music choices on Carnival to have a good variety but I do remember the Holiday cruise being heavily slanted towards country.
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise, Magic 1/14, Freedom x 2 6/14
NCL Dream October 2006, RCCL Mariner OTS June 2007, Celebrity Silhouette 2013