I understand. So you know, you can "upgrade" those files to DRM-free versions with iTunes, but it isn't free. It works out to $0.30 per track, or 30% of the album purchase price (usually around $3). As part of the "upgrade" they also up the quality of those files from 128kbps AAC to 256kbps AAC, which can be a substantial real-world improvement, depending on the source audio.
Here's the FAQ from Apple:
http://support.apple.com/kb/ht1711I think they should have offered to do this for free. A lot of the "FUD" out there is just that Apple is doing this because they're greedy. Maybe... But maybe it isn't so simple. Knowing something about how digital music sales royalties work, it is always billed per-file-transferred. That's why Apple and Amazon don't let you re-download files you've already purchased more than once, because the labels make them pay again. For the iTunes Plus "upgrade", I bet the Record Companies are counting these "upgrades" as additional sales, and demanding their full royalty payments as though you had just re-purchased them. The majors really hate Apple, and really didn't want to give up on their DRM dreams.
If this is/was the case, then Apple
could never do it for free. If so, they'd essentially have to take a loss for every single song ever sold on the iTunes store up until this change was made, which is a HUGE amount of money.
Of course, they do also like to charge for "add on sales", so who knows... Maybe it is a profit center. I doubt it though. The iTunes Music Store is chump change to Apple. They use it to drive sales of iPod hardware, not to generate huge profits.