Well, here's another interesting twist:
My local library system (I'm in Canada) lets me download 5 free songs each week.
A lot of times, only selected tracks from a particular album are
made available, but sometimes the whole album is there.
The library system pays for the original recording but, unlike with books, the library only needs to purchase one 'copy' of a recording
unlike the several copies they might purchase of a really popular book.
(As my local library also loans physical CDs, perhaps they do buy
multiple copies of those.)
So, in effect, they are giving away free copies.
I would guess this can't happen under UK law - or does it?
(When one borrows 'ebooks', they can only be downloaded for a limited
time. I wonder if something similar could be done with music?)