Or just count the cheapest alcohol available
Again it will likley be imported from countries with lower labor costs.
You need something perishable, and of low enough cost that importing is unlikley.
Bread would be a good option but has the issue that it's not as common in Japan as France, it also varies wildley where as a big mac is generally consistent.
Guiness for example is going to cost a lot to ship, or local beer could be very low quality in order to keep the price affordable.