Why are TV shows/movies so different from real life?
Because they begin and end. All stories can only be told by starting to tell them, and then stopping. But in real life, nothing begins and ends. So stories are inherently artificial by deciding what to leave out and what to leave in. There is a selection for significance - almost always an assertion that things are causally connected to each other.
Since causality is the one great unknowable in our lives - we never can be sure of the complete cause of anything - stories give us an anchor, explaining why things happen. Good science and good history give us a powerful impression that we know things, but they are never certain, and there are no final answers. The only certainty about causation comes from fiction - we know exactly why things happen, without fear of contradiction, because these fictional people don't actually exist, so their subsequent words and actions can't bring a reality check to the causal assertions of the story.
I believe that this uncontradictable causality is the reason why every human culture we know of places high value on fictional and mythic storytelling. It explains with a certainty impossible in the real world; it gives us enough confidence in our understanding of people that we can make the assumptions about people's future behavior that allow us to live and act from day to day.