You get full benefit of the license and so does someone else, but the artist gets paid only once.
What if I have a vinyl copy as well as the CD? Do I get some license contributions back as I paid twice for the license? :)
I agree otherwise, it is morally in a gray zone to sell off CDs while keeping a hard drive copy. Even though the industry doesn't adhere to their own moral rules, this doesn't justify abusing the industry, i.e. keeping files around without at least one own copy.