This night shop turned ice cream & waffle parlour has save me more than once on evenings where you run out of drinks or ice. It’s located right in the heart of the 9 straatjes and it offers a fine selection of cold, drinks, candy and mostly essentials. Recently they have started selling ice cream(?) The prices, as expected for the only place selling drinks until late, are pretty high. Also they normally charge you a small fee if you want to pin and what you have bought is under 10 €. Keep in mind that this practice is illegal as they are no transactional costs when pining.