The HD tracks, IMHO, should have been an optional download that comes with the regular CD. I have no problem with creating a car stereo-friendly version, and that even be the main version. It's just the apparent attitude of "yeah, we put 20 layers into our music, but you're not gonna hear the difference anyway because you're a metal fan and your hearing is shot. If you actually care about the music, well, wait a few months and prepare to pay again, and even more." that bugs me.
EDIT: Alternatively, offer the HD tracks + regular CD on release date, (arguably) at a slightly higher price.