There are actions they can take other than suing the violator themselves. They can contact license violators to try to reach diplomatic solutions, and they can

There are actions they can take other than suing the violator themselves. They can contact license violators to try to reach diplomatic solutions, and they can offer resources such as legal counseling for other rights-holders. They don't have to force every violator to cough up the code or face putative damages, they just have to generally make it known that violating the license is more inconvenient than following it.