Distribution costs are negligible when you just make the PDFs free to everyone, but publishers spend a bunch of money on access control, security, and web inter

Distribution costs are negligible when you just make the PDFs free to everyone, but publishers spend a bunch of money on access control, security, and web interfaces that make you jump through hoops to download the actual PDF while doing everything possible to convince you to read the papers through their (possibly "social"/"collaborative") online platform instead.