No, its still breaking the copyright law. The still did the act of editing copyrighted material without permission. It matters not a whit if they bought 1000 legit copies, they broke the law.
I think the distinction is the renting.
If it was JUST selling it would not be a violation. If I hire an editor to edit my personal copy for my personal viewing AND i am not renting it out, I don't see a legal impediment.