At the beginning, Amazon was bent on feeding your library with books. Then it decided to help you by feeding you bookshelves to hold your books, computers to write your books with and e-reading device so to read when away from the bookshelf it just sold you.
Then, Amazon remembered that readers and writers happen to also be human beings with needs to maintain the brain in good working order to fill its reading and writing functions. So it expanded in feeding you the tools to maintain the overall machinery around that brain, from sport equipment to cooking utensils for the physical well being or fashion items and jewelry to attract company for the mental well being.
Now that our bodies are taken care of, Amazon is expanding again, adding food for the soul in the form of plastic art. Is the next step food for the body through restaurants and groceries?