As to why Apple does this, I think it's simply so you can't take a friend's iOS device and sign in with your Apple ID, download everything you've ever purchased, and then switch back to their account.
Disabling iTunes Radio
Q: We have given our 10-year-old son an old iPhone to use as an iPod for games and taking pictures. We would like him to have access to the Music app to listen to songs we specifically download for him, but don't want him to have access to iTunes Radio. Is there a way to completely turn off access to iTunes Radio or block it from appearing? Even if explicit content is blocked, there is so much else we don't want him listening to (or viewing, in the case of certain album covers).
Unfortunately, there's no way to do this. While you can block explicit content — go to Settings > General > Restrictions, enable restrictions, and then block explicit content for Music & Podcasts — this may not catch everything. And, as you say, your son can still see album covers in iTunes Radio. It's surprising that, while you can block access to the iTunes Store in the Restrictions settings, you can't do this for iTunes Radio.
Move iTunes library while retaining Date Added?
Q: Is it possible to move an iTunes library to an external hard drive on another computer and maintain all metadata, most notably the Date Added field? I'm ready to move my iTunes library to an external hard drive connected to a new Mac, and I want to maintain this field, as many smart playlists are based upon it. I failed the last time I tried this; every track bore the date that I moved my library.
I had the same problem when I did a clean install on a new Mac and then copied my iTunes library. Moving it to another hard drive isn't a problem — if you use iTunes' method of moving and then consolidating the library — but once you put it on a different computer, iTunes gives the library a different internal ID, so it will see the files as new. I don't know of any way to make that change to the files themselves.
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