As others have pointed out, restaurants mark up wine by quite a bit. And as another poster said, add a few additional bucks because it's Disney. Because of this, it shouldn't be TOO surprising that you found that same wine for $12. That's why I was wondering why you thought it couldn't be the same stuff.
As a little tidbit of wine trivia (I'm a huge wine buff in addition to being a huge Disney buff), different wines are marked up differently by restaurants (i.e. they are not all marked up by the same percentage). As a general rule, the wine that is usually marked up the most is the one that is listed on the menu as the second cheapest. This is based on the fact that most people who don't know much about wine will usually order the second cheapest one on the menu. This is because people don't usually want to appear "cheap" by ordering the very cheapest one. But they tend to think they are still paying a relatively fair price if they go with the second cheapest one. Restaurants know this, so they often mark that one up the most.