With great fiction, the reader tends to forget they are staring at words on a page - and begins to imagine themselves in the story.
Sometimes they are they identify with the narrator or protagonist, other times it's another character - but identifying with characters is the key to an engaging story.
Even in the most out-of-this-world fantasy story, it is the small realistic details that make the characters human and believable.
We see ourselves in them, and identify with their feelings and actions.
For example, when Harry Potter is nervous and excited about returning to Hogwarts at the beginning of the school year, it's the real-life things he does and says that help us understand how the character is feeling and experiencing.
Although very few of us go to wizarding school, we can all identify with the jitters that come with a new school year.
So that's why including real-life events and situations can really drive your storyline. It encourages readers to connect and identify with the characters and their journey, and makes the plot more believable and riveting!