Instead of printing and mailing costs, there are HTML and other development costs, Internet service costs, and systems administration. These Internet and develop costs could easily exceed paper, printing, and mailing costs for some journals. Many struggling journals cut corners, taking the cheapest route, hiring non-professionals to do their technical Web development. However, the myth that technology somehow erases production and distribution costs isn't accurate. The truth is that the real tough part of Web publishing isn't technical development.
Online communication does help in certain kinds of information exchange.
Again, the technology does not erase these costs. Indeed, the training, equipment, time, and extra effort that may be required to manage the sometimes obscure complexities of file formats and managing the delicate sensibilities of authors in an online medium may indeed contribute to more costs over what that journal would cost if published on paper. Where Web publishing makes cost-effective sense is in publications that do not claim to have institutional authority nor have any commercial viability as a paper publication. For example, my magazine, Computer-Mediated Communication Magazine, is not an academic publication. Although I employ an editorial process that takes a rigorous approach at content acceptance and review, I make no claims that my publication is peer reviewed.