I'm not sure you understand what academic publishing involves. Academic journal editors are paid a pittance (few thousand pounds a year), and they are the ones

I'm not sure you understand what academic publishing involves. Academic journal editors are paid a pittance (few thousand pounds a year), and they are the ones who pick the reviewers. So the journal publisher is doing nothing to select the reviewers, and is not acting as a great middleman. The board of editors could do this job just fine without the journal publisher. Reviewers themselves get paid nothing at all. In CS, the journal publisher/ conference proceedings publisher does nothing to organize the editorial board or pick reviewers. For conferences, there are a couple of Program Committee chairs, and they pick the PC that then review papers and solicit external reviewers for help. Once again the publishers have no role to play. Electronic journals such as Discrete Analysis in mathematics are already doing a decent job of offering cheap open access to articles, and have a solid board of reviewers.