I read that Carnival Cruises levies a 15% bar tip on all bar orders... then I heard that soda pop is available at the bars only.. Does this mean, that there will automatically be a 15% tip added to my S&S card for each can of pop I purchase? What if I purchase the fountain pop card, would there still be a 15% tip added to my S&S card for each fountain drink I ordered on my fountain pop card? Are there pop machines elsewhere on the ship?