That's because that journal is doing it wrong and someone there is getting too much money. You give me 3k and I'll seed a torrent for one thousand papers as long as my Internet is billed per month instead of per GB. I just saw some redditors link a torrent with tens of gigabytes of technical books, so the method appears to work just fine. And if the author's intent is to distribute it wouldn't be violating anyone's copyright.