Birds absolutely have taste buds. I have a bird (and also volunteer at a bird rescue) and birds definitely have food preferences. A lot of the time, they like sweet and fatty foods (like nuts and fruits). These tastes are preferred by many creatures because they mean that the foods in question are high in energy (calories). One interesting thing that I have read about parrot taste buds is that they can enjoy the flavor of hot peppers without feeling too much of the heat!