I actually have a partial answer for that.
It's because any album released is basically free to download via you tube or various other means.
This also applies to an artist's back catalog.
Owning physical media in now unimportant to many, many music consumers.
The exceptions are special releases and to an extent, vinyl.
Instead of airplay and album/single sales royalty checks rolling in, not the difference is made up for with what seem like exorbitant concert ticket prices.
The ticket master monopoly sure doesn't help, though.