Weird Al and a Messed Up iTunes Deal

In an “Ask Al” feature on his website, Weird Al Yankovic answered a question as to whether he makes more money from a traditional CD sale, or from a song purchased on the iTunes Music Store. His answer (on this page, fourth question from the top) indicates he makes more money from an album sale than he does from a download.

That makes no sense (and Yankovic admits he’s baffled as well). There are essentially no per-sale costs associated with a download… no physical packaging, no artwork, and no shipping or storage fees, yet as an artist he makes more money from the sale of an item which has all of those overhead costs. Is this an oddity or are most artists in the same situation?