For some people, it simply does matter whether they own copyrights to a song or not.

For some people uploading a song they do not own is not a problem for them, like this YouTube star who has clocked up millions of views on YouTube. 

What the heck, who cares about potentially being sued for millions of Pounds anyway? 

Maybe he's letting people know that in the event of being sued, he owns no assests available for sale?