Remember, Bob Iger said it's okay to go against what Walt explicitly said about alcohol in the parks because Walt himself drank alcohol. So problem solved.
In all seriousness, I know that we often get hung up "what would Walt think of this" kind of debates. And in most cases, it's just all idle speculation with no possible real answers. But these isn't speculation. It isn't a "what if." This is a specific issue that Walt himself dealt with, made a decision about, and is on record about. He did not think alcohol should be served in his theme park.
Are the leaders of the company bound to honor that today? No, of course not. But of all the "this isn't what Walt would have wanted" arguments that come up, I think this one is at least the most solid.