I also download songs so that I can discover artists and listen to tracks that are not readily available on CD, such as live bootlegs and b-sides.
I do not support downloading and never buying an album. I believe this is wrong unless the person doing so has a financial trouble which keeps them from purchasing music.
The primary reason I buy CD’s is to support the artists that do the amazing work of creating music. While so much often goes to corporations, the artists still need to be paid for their work, and certainly deserve far more than they get.
I purchase CD’s because it is important for me to have hard copies of the music I listen to so that I can be sure not to ever lose a single song (for computer crashes do happen).
The artwork is also valuable to me, because it adds another layer to the experience. Many artists put a lot of time into the packaging of their works, and that should not be ignored.