The phrase "can you bring your own soda on a cruise" refers to the question of whether passengers are permitted to bring their own non-alcoholic beverages, such as soda, on board a cruise ship.
This issue is relevant because cruise lines often charge high prices for drinks on board. Bringing your own soda can save you money and allow you to have your favorite drinks on hand. In the past, many cruise lines prohibited passengers from bringing their own beverages on board. However, in recent years, some cruise lines have relaxed their policies.