Who pays for the academics who spend their lifetimes researching the field we're reading about?
Who pays salaries so the best people can make a living doing what they're truly great at?
Who makes enough money to get big and old enough to gain a reputation? Without which, the news is a hail of unsubstantiated bulletins from semianonymous writers, a wilderness of mirrors and fake news amped up to eleven?
Believing that we can make content totally free is utopian. You might as well ask why to bother paying software engineers large salaries when open source software exists.
In a world where content is free, all that happens is that newspapers become the organs of plutocrats and political groups. If you want to imagine how the internet looks when content is totally free, imagine a Facebook news feed written by the Koch brothers.