These leaks frustrate labels and artists and not just for financial reasons. Many musicians work months if not years on their tracks; seeing these being paraded on pirate sites, before their official release, stings.

I dunno about this. Most of the artists I give a shit about have their music up for free on Bandcamp. The ones I've asked point-blank about it have said that they don't care about piracy; they see it as free advertisement for their live shows, which is where they make most of their money (and on merch sales). This might be true of some of the largest acts, where sales might make up more than a few hundred dollars in total annual revenue, but probably a lot less true for most mid-sized or smaller acts.

OTOH, given that the labels are the ones making money off sales of music, they probably care quite a lot.