Journals provide a valuable service, but I don't think that exclusivity is a necessary component of that service. The people buying the journals will (probably)

Journals provide a valuable service, but I don't think that exclusivity is a necessary component of that service. The people buying the journals will (probably) keep buying them even if they can legally get the papers for free elsewhere, because getting a physical copy of the paper was never the point - curation and peer preview are what subscribers are really paying for. Of course, this goes both ways: if journals start publishing crap to cut costs, people will stop buying them.