Before criticising folk who use iTunes you have to consider the following:
1) Apple managed to get a sensible sales model from the major music labels. You need to look back a decade or so to see just how crap the industries own on-line shops were. Just who gives a fsck about which label your favourite band is on? And the incompatible DRM shit!
2) Some folk struggle to use ripping software. Hell, some struggle with the concept of RTFM, or even of using Google, etc, to find help...
3) A lot of folk bought Apple ipods, etc, and they deliberately did not document the interfaces and often changed them, so getting music on along with album art was hit and miss. Same trick MS has used...except nobody bought the Zune...
4) A lot of new laptops, and all tablets, lack CD drives and few folk will splash for an external USB one unless they can be persuaded of the benefit. Buying the CD may be comparable to, or even cheaper to iTunes in the sale/bargin box case, but buying one track at a time is popular because frankly a lot of albums are pish, with one or two redeeming tracks. If you are lucky. In that case the economics work against CD purchases.
5) While CDs are uncompressed and better than half of the MP3 tracks out there, most folk don't seem to care about Hi-Fi quality. They play them through crappy speakers or headphones and often as background music, and just don't see sound quality as important.