This video takes a quick look at fan use policies, which are put into place by publishers to allow fans to use their intellectual property.
Some fan use policies are comparatively open, such as the from Monte Cook Games that allows content to be published for Numenera and The Strange, and even for money to be, indirectly, made from it.
Others, such as Paizo’s Community Use policy for Golarion, won’t allow such as a publisher to even do something for free.
So, which is better for a publisher? Clearly, publishers have differing opinions.