How can people give away Premium Themes for Free?

I am a fan of envato themes for many years and I have purchased many themes which are running successfully on my client’s website. I happened to come across few sites like themekiller.com, jojothemes.com and many such sites giving away almost all themes listed in envato marketplace for free. I would like to understand why no action is being taken on these people who crack the code and remove the licensing and give it free of cost, thus causing lots of injustice to the people who have created the themes. The developers and authors of the themes would have put in so much efforts to get it functioning and here you find guys who are breaking the code and giving it as a freebie. Isn’t there any laws to penalise such people.