It's about some mice who own a restaurant, and other mice come to this restaurant and really like it, because of secret ingredients and things of that nature.
These secret ingredients that are very much enjoyed by customers are stolen by the restaurant owning mice from cats, other kitchens, and things of that nature. These ingredients are brought to the restaurant and cooked in the food. As can be seen there is a vicious cycle in the repetition of having to steal ingredients to make food to satisfy customers-- this is symbolic to the monotony of every day life and labor.
The restaurant owning mice are alienated from their lives, as they spend most of their waking moments laboring, either in the restaurant or stealing from cats. The source of their alienation is their vulgar profit making motive-- as they obtain the ingredients to enhance their cuisine not through exchange, but through stealing. Our owning mice are placed in the situation where they have to steal as they cannot or choose not to interact and exchange in the marketplace to obtain the secret ingredients. Such desperate measures lengthen the working day and thus their alienation.
This alienation is expressed by the animators with the thread bare backgrounds, and scenery. Nothing retains any sense of texture, all is smooth-- the characters don't appear furry, neither does the background range from course, splintery, or downy. All visual stimulation is sucked dry-- the characters are lifeless and soulless.
Oh I haven't watched the film yet, I don't intend to, because it looks like it sucks horribly.