Am I totally imagining, or did Amazon at one point actually run the web site for Borders? I may be confusing them with Target, who I am certain did use Amazon for their website, about 10 or 12 years ago.
Borders did have a good music selection, but much of it was overpriced compared to other brick & mortar vendors where I lived at the time (and possibly none of whom still exist). Come to think of it, Best Buy had a very good selection for a while, up until 1996 or 1997. (I discovered this at BB, and found this one as an import when it wasn’t in print stateside.) It was as though someone who knew what they were doing stocked all the music for BB stores in the early- to mid-90s, and when the good merchandise ran out (or that person/team quit), BB never put in any more effort beyond the music dept. in (for example) a Target store.