> Copyright does not cover use
Copyright does cover use in many (most?) countries, especially EU countries.
This difference between US and EU author's rights has been widely debated for the JSON licence that states "The Software shall be used for Good, not Evil.", making it a non-free licence because it restricts the field of use.
That said, I'm not sure if downloading the source from Github constitutes any form of reproduction or distribution. From what the page you linked to says, that may be covered by Github terms of service.