Since when is how much we get from something tied to how it impacts us? Watching a movie doesn't change us physically, but we pay $12 for it because it entertai

Since when is how much we get from something tied to how it impacts us? Watching a movie doesn't change us physically, but we pay $12 for it because it entertains us, just the same as most digital goods. I don't pay $20 for a book because I want a stack of paper, either. If that was true, you'd get paid to smoke and eat fast food, since they have a negative impact.