There are many examples of print publications making a market for antiques or collectibles. Wallace Nutting prints and Nippon china. My own experience bears this out. Interest in this collecting field grew visibly, and new auctions even sprang up. They can do this nationally and internationally, because Web search engines allow readers to find magazines of interest rather than the publisher finding interested readers.
Similar arguments hold for collectors' organizations.
A collectors' club can produce an inexpensive on-line magazine for its members. Potential new members may discover it surfing the Web and become interested. On-line magazines will not replace print publications. The Maine Antique Digest could take the better part of a day to download on a dial-up connection, and it would not be handy to read on a computer screen. On-line magazines can fill a need, however, in specialized fields that cannot support a large publication.