There are students of all ages who struggle with reading, for whom reading just a paragraph requires sounding out every other word. For these students, being read to can remove the barrier of having to process written text. Of course, there will not always be someone present to read to these students, but hearing a book on a topic they particularly enjoy can help diminish the "books are stupid" attitude that their struggles may have led them to develop. Such students might never read "War and Peace" as a result of being read to, but listening to stories might keep them from giving up on reading altogether.
Students today live in a culture where most of the media they consume comes in the form of flashy visuals and smoothly designed sounds. While hearing a story being read might not have the same production value as a movie or music video, simple things like the spooky voice their teacher creates for a ghost, for example, can improve their engagement. Listening to stories is not meant to be a replacement for reading them but, rather, an enticement to show students how much enjoyment they could get from reading on their own.
Many children, sometimes even those who are by no means poor readers, tend to read rather flatly when asked to read aloud. When teachers read aloud to students, they're able to convey the subtle cadences of sentences that students often miss on their own. Listening to stories may improve students' comprehension of literary elements such as tone and mood. Furthermore, listening frees up the parts of their brain that would otherwise be occupied with processing the letters and words on the page, and allows students to better visualize what's happening in the story.
When teachers read stories to their students, they're not only improving their ability to listen to stories but also their ability to listen to all forms of oral communication. Being able to hear what people are saying and quickly and correctly process the meaning of their words is a skill required in nearly every career field, not to mention in many aspects of life. These skills will not only benefit students in the future; being a better listener can improve their social and family lives right away.