The shopping was at Christmas time. There is a lot that is inferred because of what is NOT said. With each word, new ripples are created into the reader's consciousness. Notice how the story is much shorter than the list of propositions following it. This is because narrative is deeper and richer than other modes of knowledge transfer.
Stories are often a more compact way to express an important idea.
Not only is the story above much shorter than the list of propositions following it, but it is also easier to understand and easier to remember . When we read the story, we create an image in our minds that is whole and internally consistent, and we can use that image as a setting for any points that are made. Also compare the story fragment and the list of propositions on how interesting they are. Just watch what happens after a speaker finishes a story and goes back to his or her prepared speech. There is usually a distinct rise in fidgeting when the story is clearly over.