There was no store in iTunes when it was released in 2001, and those of us using SoundJam MP knew there would be no further updates so we started using it and enjoyed its bulk metadata editing and album art embedding capabilities, with an interface that was intuitive for managing playlists and music. And scriptable!

It wasn’t until two years later that the store was integrated as part of an update.

Although there was an (Carbon?) OS X version for a while, Winamp was Windows-only from what I knew, so my opinion of it was always coloured by having to use Windows to interact with it, although I used CrossOver on Mac and Mint as well.

EphPod was 100% free and didn't bury its functionality in an Advent-calendar UI. It was simple, clean, and did something that iTunes/Music doesn't to this day: automatically sync new files you added to your music directory, with no need to "add to library" every time you acquired them.

iTunes, when tied to a "megacorp's business model," still suffered from piss-poor UI. Take, for example, the "LCD" display at the top of the UI that was even depicted as having a transparent cover over it... yet had undemarcated clickable controls in it (which you were likely to never discover).

So I don't see the relationship between good or bad UI and business models in this case.

Some people don't enjoy meandering through a puzzle game of arbitrary, standards-ignoring UI instead of getting stuff done.