There is an alternative - instead of removing a layer of the CD, you can add one.
I keep seeing commercials for this product, and I don't know how well it fixes scratches, but it's supposed to work well to prevent them. It's a thin sleeve that you snap over your disc.
Their main website,
www.d-skin.com seems to be down at the moment, but there is
this review if you want to read a little more about it.