The term "Soda" may mean different things to different people from different parts of North America. My wife considers ice tea a "soda" because she can buy a can of it from a soda pop machine.
The OP was probably refering to the free Lemonade and Ice Tea provided in the Windjammer.
Majesty of the Seas - 10/03 & 02/07 & 11/08
Enchantment of the Seas - 10/04 & 10/11
Mariner of the Seas - 10/05
Vision of the Seas - 10/06 & 09/07
Carnival Liberty - 10/07
Adventure of the Seas - 9/08
Ruby Princess - 12/09
Voyager of the Seas - 9/10
Carnival Spirit - 11/10
Oasis of the Seas - 9/13