This confuses the hell out of me. Why would you make a CD loud and distort the sound when there's a volume knob? It takes just as much (or little) effort to turn the volume to 30 as it does to turn it to 10.

Albums like Death Magnetic are particularly egregious examples of this, but I think that every CD suffers somewhat from this obsession with making the CD itself so damn loud. We have amplifiers for a reason.