They are designed for specific jobs or roles, they're conditioned to be obedient to regular humans, and they're not citizens. They are, in short, slaves. In a lot of books, that's as deep as the analysis would go.

I supplement the rest of my nutrition with vitamins and protein powder mixed with water or milk. She and her son came to my house unexpectedly when I was eating my carefully planned sandwich/chips/soda ration for that first day.