Hmm, that's not the case on my disc. I can hear the backing vocals clearly. Try playing it on another device.
In YBTTC, the part at the beginning with bass & drums pounding, just after the sax, has been remixed to emphasise the drums rather than the bass. This is a significant difference.
I can't discern much of a difference on my disc either, but I'm not listening with headphones. Maybe some other folks would like to weigh in?