Yeah, I still buy CD's. I simply like to own the physical media even though they get burned to my hard drive and are than likely never to see the light of day again. That said, the metadata entries on many are just simply awful. I just bought the 50th anniversary release of the the Grateful Deads Skull and Roses release and it split Disc 1 up into two separate entries in iTunes. Long story short, my attempts to fix it failed and it's just easier to re-import the disc and start over. Thats just one example. I've got entire boxed set collections that has the wonkiest meta-data entries imaginable. It's really quite annoying and I don't know how it gets past any kind of internal Q.C.
Because there are only two ways to get metadata uploaded: Automatically, which is frought with error and will be for the forseeable future (you can welcome your new robot overlords all you want, but until there is AI that can tell when a comma between "bass" and "guitar" is intentional or a typesetting glitch, all bets are off) ...or manually, which takes time, money, and a committed/attentive individual who is personally interested in the accuracy of their work.
Where does the metadata come from? The manufacturer? Maybe it’s not worth the expense to do that well if they don’t sell many cds.
Because Apple's metadata database contains data that is manually entered by human beings, which invites errors. I've had to fix more than a couple of track titles when importing CDs. EDIT: On several occasions, iTunes asks me which version of the CD it is. If you pick the wrong one, the information about the tracks could be wrong as well.