That was a regular currency overseas between civ contractors and military. I think it would never be a regrettable store, even if it is never used to barter with militarized forces, it would always be a "luxerious" trading commodity. I try to make a 10 gallon batch of homemade wine every year to perfect the craft (accoeding to the last batch, I have a few more practice years to go). Seems to me that there would always be a demand.