"Get over the summer with the vinegar stamina drink!" is on the sign.
I am not sure how much does it cost to provide sample vinegar per day, but it seems that the shop is making it, considering other shops in Kimobetsu town and Otaki Village in full flourish.
All the mushrooms sold in this shop are produced in Otaki Village near the area. The flavoured mushrooms in bottles are worthwhile. A veggie and fruit shop that sells materials sourced locally is next to this shop. Thousands of tourists drop by this shop with huge parking lots. Before winter comes, hit the road and romp around in Hokkaido!