Actually, a lot of people are apparently doing this on auction sites. Some of the new ipods and new MP3 players can hold HUGE collections of music (like on the order of 5-10K worth of music as estimated by the retail cost of buying all the CD's individually or in collections).
So someone who doesn't respect copyright can sell their whole music collection over and over again (because they are selling the ipod for MORE than you would buy it brand new), and it's essentially disguised as selling a new ipod as opposed to selling "pirated music" which is obviously illegal.
Bingo. You explain the RIAA rationale better than they do.