It's about tragedy of the commons. When each person is looking out for their own interests, they might not think that e.g. filmmakers are worth the millions of dollars it takes to make a movie. Then out society wouldn't have any big-budget movies, and we'd all be worse off. But of they get copyright and can charge theaters for showing the movies, then they can make the movies. And our society in general is better off.
"Then out society wouldn't have any big-budget movies, and we'd all be worse off."
That is quite a leap of logic... Though it is interesting that you use the example of film, considering how often film so often lifts from the public domain.
(from above) Scarcity is the root of all Evil. Copyright increases scarcity.
(conclusion) Copyright begets Evil.
A bit Old-testament, mind you, but I really do believe this to be the case.
You are absolutely correct in the idea that without copyright modern cinema (for example) wouldn't exist.
The problem I have with your example of movies is that there are many assumptions being made that I don't think are reasonable: we don't "need" big-budget movies, society isn't automatically "better off" because of the movies, and the movies don't "need" to cost as much as they do.
If movie production had to be paid for, up front, before being made and put to film, this would be fine. You would bet your ass that "Hollywood Accounting" would disappear, because the margins would be too slim to allow otherwise.
You have a pile of money and expectations that you'll make a movie; if you don't pull it off, you are publicly shamed (thank you Internet!) and never able to raise a cent again. If you do pull it off, you got payed (you did factor in cost of your time in your budget quote, right?) and the people got their movie. If it's pirated it doesn't matter because it was already totally paid for. It's a wonderful thing.
The Great Pyramids of Egypt and the Great Wall of China and the World archipelago in Dubai are all amazing achievements--but would you ever pay for them today with a straight face?
For good measure:
Consider the top 50 most expensive films of all time ( http://en.wikipedia.org/wiki/List_of_most_expensive_films ), and then consider how much money they brought in. The entire system was a "valid allocation" because of copyright guaranteeing a return on investment, whereas otherwise it never would've gotten made ("So, you want me to pay you $20 so in 4 years I get to watch a movie about the Titanic?").
And now think about how many people in the US couldn't afford medical care. Or couldn't afford housing. Or couldn't eat healthily. Or couldn't afford education.
This, while the very society and civilization they've ceded control of their lives to goes to great lengths to ensure the unequal distribution of goods and services! Goods and services that ought to be free to duplicate!
The whole thing is an embarrassment to our species.
I don't mind for a damned second paying for a project, but I most certainly mind subsidizing thugs to beat a captive market while people are suffering.
~
I'm not against movies, art, music, literature, or whatever else. I just think that regulatory capture of modern copyright (and for that matter, patent) law is more trouble than its worth.
At the end of the day, you do realize that the endgame of this all is not being able to tell another human being a story or sing them a song or show them a picture without paying a fee somehow?
Copyright is enforcing the idea that that most noble of pursuits--sharing, alleviating that one great Evil of scarcity for your fellow man--is somehow wrong. It's disgusting.
It's about tragedy of the commons. When each person is looking out for their own interests, they might not think that e.g. filmmakers are worth the millions of dollars it takes to make a movie. Then out society wouldn't have any big-budget movies, and we'd all be worse off. But of they get copyright and can charge theaters for showing the movies, then they can make the movies. And our society in general is better off.