Unpackaged prepared food that requires no additional preparation before service may be

The answer is bakeries, subways and fresh food restaurants. It is because they need to serve it in a preparation such as read above because having it prepared that way is more beneficial to them so that the food won't get spoiled and wasted. In the same time, it is for the safety of the customers so that they won't consumed food which are spoiled that could lead to food poisoning.