"Great Classical music you're playing"

The "hold" music on the Spokane Public Radio telephone system is the KPBX signal. Today during the Matinee show, someone called for me -- it was during the segment of Florence Henderson and Robert Weede singing in an operatic style. The gentleman coming off hold commented, "That's great classical music on right now."
Classical music. Jazz. Soundtracks. Musical theatre cast albums are constantly pushed into categories they don't belong in. If you ask a classical music aficionado where to find theater music on a shelf, they'd suggest jazz or soundtracks. As a jazz lover, and they'll most likely say classical or soundtracks. I've never met a real film soundtrack fanatic, but I'd guess one would know the difference between a cast album and a soundtrack and want cast albums to go into classical or jazz.
Where does this confusion come from? Is it lack of interest? Lack of education? Or is it confusion from the cross-over appeal of certain songs? Tin Pan Alley cranked out the songs aimed at both the professional stage and sheet music for pianos in living rooms. For decades, a show couldn't be considered a hit unless it had at least one song that made it into the American consciousness. Add in Ella Fitzgerald's Song Books, and all the other jazz interpretations of musicals over the years, and there is reason for confusion.
On the classical side, the main difference between a symphonic orchestra and a pit orchestra is size, not instrumentation. Opera predates symphonies. The general thought is that opera begat operetta begat musical theatre (John Kenrick's excellent history of musicals is at musicals101.com). The Boston Pops and countless other orchestras interpret musical theatre overtures and tunes into 'lyricless songs.'
But none of those reinterpretations, either classical or jazz, are the same as a 'cast album.' They don't have the same emotional resonance of an actor or actress putting the song into a show's context. They don't tell the song's story the same way. Cast albums are cousins to jazz and to classical music, but not siblings (or bastard children pushed away into the other group's camp, as it seems to be).
Only the real lovers of Broadway music seem to want cast albums marketed as CAST ALBUMS. Billboard got the message a year ago, adding the "Top Cast Album" category to the best-selling recordings lists. Who will be the next to understand the difference and give it the respect it deserves?