Hi Jim,
I see where you're coming from, but I'm not sure that I would fully agree with the above comment. There are plenty of magazines that are not that informative, many of which you can find on your local bookseller's shelf. I would argue that access to good, original information is what makes or breaks a source and separates it from the "commodities" that you mention.
You hit the nail right on the head that there is only so much ad revenue to go around and that is indeed a limiting factor. To be quite frank, I don't like to have to chase after that with my hat in my hand, nor having to worry about offending an advertiser due to the articles we run, or because of what forum members (which I have no control over by the way) post or say about them. As far as I can see, online and free is the only way to go and keep things fun and interesting for everyone and especially for yours truly.
Even the Japanese koi mags aren't making money, and at least 2 rely on funding outside of their normal revenue. I hate to think what will become of them a few years down the road as some of the older folks that help sponsor them begin to pass on. Not a happy thought.