[PeterisP]

It's not depriving authors or the reviewers of money, since they don't get any money anyway from publishers or readers. It is depriving publishers of money by replacing them, doing the same thing they do (intermediary between author+reviewer and reader) better and cheaper i.e. for free - but that's essentially just outcompeting them in their own business. Copyright is there to protect incentives for authors, but it should not grant an artificial monopoly to useless middlemen.