I believe, "don't ask don't tell" applies here. My interpretation of the customs form only requires me to list dutiable or restricted items. One liter of booze. Not dutiable, not restricted by customs law AFAIK. Therefore no need to itemize it. Simply include it's dollar value in the value of stuff bringing back box. 95% chance they take your form and send you on your way without ever looking in your bag. 5% chance you get sent to secondary for some reason, where the nice officer explains to you the problem with your logic and you loose you booze with no further consequences. Not even a slap on the wrist. So 95% odds of success and no major consequences if it doesn't go your way. (unless it is very expensive wine). Them's pretty good odds in Vegas.