The Shinobi Shop is a location related to the mechanics of points of interest and Challenges, where players can trade and sell resources obtained during these activities.
buyer
The shop features a buyer to whom you can sell resources farmed in points of interest and Challenges.
Thus, unnecessary materials and items obtained during these activities can be exchanged for in-game currency.
Trader
There is also a trader in the shop offering various exchange options.
His offers may include resources obtained from points of interest and Challenges, allowing players to get needed materials in exchange for other available resources.
The trader's stock is designed for additional use of the resources farmed during these activities.