I believe that at some point in our lives we have all heard from someone that it's a waste of time to watch films. Perhaps it was our parent, teacher or one of our family members who said it with a straight face while we were enjoying ourselves in front of a screen. And we all probably felt guilty at the time, although we probably didn't know why. I have felt that guilt myself many times. But when I was older I started to watch more and more movies and to think it was fair or unfair.
Let me give you an example of how. At first I did not speak English well.
I could read and write, but not speak or listen very well. But after I started watching English movies and TV shows I didn't know that I improve my listening. I began to pick-up words and phrases I have never learnt at school. I began speaking with different accents and dialects. I started feeling more familiar with the language as a whole. And that because I was watching something that I liked. I don't think people would consider that a waste of time.
Films can depict for us different lives and circumstances to what we have known. A person who has never been overseas can learn about a different place, a different time and a different culture by watching a film. Someone who has never had a tragedy in his or her life can watch a movie and learn to understand the feelings of those who have. I believe that emotional learning is what can't always be found in the classroom. Sometimes a two hour film can make a person feel and understand something more deeply than years of formal learning.
On the other hand I will also say that not watching films is the same. It is not the same as watching something for hours on end to pass the time as opposed to watching it because you are interested. I have experienced both and I feel different after them. When I watch something that stretches me, or makes me cry or informs me I feel fulfilled. When I watch something that challenges me, or makes me cry or educates me I feel satisfied. When I watch something for too long out of boredom I feel hollow and remorseful at how I spent my time.
I don't think it is the movies. The problem is the intention and the balance. If you are not doing anything with intention and balance, you are wasting your time, it could be movies or anything else.
To be honest I think movies are one of the most underrated teachers in the world. You don't get a diploma and I think this is why people don't pay attention to them.