Chinese style ducks
A friend, the owner of a Chinese restaurant, described his duck recipe to me once. Peking style duck (the recipe, not the bird) involves inflating the duck with air and roasting it, so the skin is thin and crispy and the fat renders out. Part of getting the skin crispy is that it fries in the rendering fat, as the duck roasts.
So, by necessity, a duck that is designated for Peking duck recipe should have the fat necessary for the preparation. Therefore, while a Chinese market may have a duck for sale, it might be a fatty duck, intended for that type of preparation.
Be aware of that, if you are looking in Chinese markets for duck.