It's just exactly as the title suggests. A good thing to expand the Gold shop could be adding sketches as an item that can be bought. Maybe 5 gold coins for a 100 sketch pack with a 5-item purchase limit? Idk, I'm not a game developer so this can probably use some more thought about balancing. But since sketches are clearly designed to be bought with real-life money when they run out for those people with the means, I think that kind of cost and limit is sufficient.