I've yet to see any justification at all for the outrageous fees charged by academic journals.
The only costs I can see are printing/distribution and web hosting.
Typesetting is trivial. Editing is non-existent. Editorial isn't paid. Peer review isn't paid.
Having a nice office and marketing staff who hold university libraries to ransom shouldn't count as a cost.
The second point is that publishers costs are around 70% of revenue, as the article says margins are around 30%. That means there's a limit to how low they can go and not lose money, and I doubt many of those complaining would suddenly stop if prices were 30% lower.
Oh it does count. Peer reviews in journals are done by scientists for free. Peer review adds completely negligible costs (or even ZERO) to a journal. ArXiv is the perfect example.
Then can you explain why arxiv costs around $10 per paper, while plos charges over 100 times as much?
They just increased the fees for their general purpose publication, PLOS ONE. Here's their reasoning:
"PLOS ONE has not increased its Article Processing Charge (APC) since 2009, for the past six years absorbing increasing publishing costs without raising author fees. Its new price reflects the work involved in shepherding the volume of papers PLOS manages from submission to published work; PLOS invests significant resources to improve the quality of PLOS ONE output, thoroughly checking for ethics, competing interests and robust science."
They also say they're updating their terrible article submission system. I don't see how any of this costs as much as it does. PLOS ONE alone publishes ~30,000 articles a year, that's a huge amount of money in fees, even if not everyone pays. On top of all of that, they accept and publish 70% of all articles. That's a really leaky sieve that shouldn't be so expensive to maintain.
So consider $2250/article as a representative price in the PLOS suite, by 35 articles by 12 issues - About $USD950,000/annum revenue per journal. I wonder how that compares to revenue/issue for the traditional subscription model augmented by online fees? I looked at Elsivier and Wiley's financial statements but there wasn't enough info broken out to guess.
EDIT: closer reading of Wiley's statements [1] suggest $1.385 billion revenue from journal subscriptions with 1600 "scientific and professional journals" in print, for revenue of $865,000 per journal.
[1] http://www.wiley.com/legacy/about/corpnews/fy15_10kFINAL.pdf