not always impractical (Score 1)

I don't know if this has already been mentioned (didn't feel like reading all of the replies), but selling a song for $.99 could be useful in some situations. The Apple exec says that it doesn't make sense to sell a song you bought for $.99. What if you wanted one song on an album that was only sold in whole. In this case you could possibly sell off the excess songs and make back the money from those extra songs you didn't care for.

Granted, you probably wanted the one good song on that album and the extra sludge would not sell very well.