What can you judge without having seen it read it etc.?

I keep hearing people say that whether it is about a movies or books or many other things. “How can you judge it without having experienced it?” But who has the time to experience everything first hand? Nobody would have any time left to eat, sleep,work ..
Why do people say that? The movie Hunger Games for example Have you seen it? What do you think? What did you learn from it?