The answer could fall under the master plan theory. As this whole thing was set up from the beginning. Christian, Anthony Cooper, Desmonds gf daddy, are all apart of a bigger identity then what they lead up to being, Hince the reasoning of having the same whiskey. Which also makes you ask who had it on the plain?
I hadn't thought of that, but it makes sense. I have actually been looking for it in different bars and restaurants lately, so that I could see what the big deal was, and not many places have it. The fact that it popped up so many places, including on the plane and in Ben's house, seems to point out that it is the liquor you have on hand for when the boss shows up! Or, the gift the boss gives you for doing a good job, or something like that. It would seem to tie Widmore, Christian, and Ben together, at least.