With no recourse when people ignore you. So what exactly would be the point of a license? The entire concept exists because legal systems exist.

Anarchism doesn't allow for the organized defense of property rights by definition. Otherwise, you're right back at government. Using licenses and legal systems to protect products or property rights is a pretty shitty example of an anarchist. You don't even own products under anarchism for the aforementioned reasons. There's no real way to enforce such a concept as product ownership.