If a publication is interesting, informative or educational it will initially appeal. I say initially because thereafter, unless you become a fan of certain regular contributors, once your "informed" you likely will have no further reason to buy them.
Not so many years ago, If you were new to angling or wanted to learn new methods/techniques then you would most likely subscribe to the idea of buying and reading mags. Nobody ever buys them for the sole purpose of reading advertisements but unfortunately just like TV channels, they need to sell advertising space in order to survive. bait & tackle reviews are available from respective manufacturers websites these days if that's what you want, or better still, good honest reviews by others, recommendations etc. are abound.
Same goes for any subject of interest, I remember buying and learning how to count in binary from a book in or around 1973/4 which also included a schematic of a modular calculator which I later built over the course of a year out of my pocket money. This was in an era of when the first pocket calculator would cost a small fortune to buy, and a year or so before Microsoft was founded, these days calculators are sometimes given away free they are that cheap and almost everyone now owns a PC. I also bought various engineering books and modelling magazines, computer magazines when I first started building my own computers in 1995, fishing magazines when I first started fishing in 1968 etc. anything that was of interest to me has followed a similar pattern. If I needed to learn, I would buy the book or mags. Once I had mastered the basics I would no longer have the need to buy them. These days there is no longer the need to buy books or mags at all if one chooses, the Internet has everything you could possibly want mostly free, covering all manner of subjects if you know how to search for it.
I think Magazine publishers that are starting to archive content online is the natural transition to what will eventually become the future of magazine subscriptions. As long as they are SEO and searchable/indexed and accessible they should do okay in the short term. Unfortunately though it doesn't necessarily always work out favourably for the publishers looking for paid only subscribers, Encyclopaedia Britannica was an early adopter of online content archiving (Encyclopædia Britannica Online.) as a case in point, apart from institutional subscribers who now subscribes to that? (a quick search reveals only 15% comes from subscriptions to the consumer versions). Their hard back volumes were once the household bible of knowledge at one time for those that could afford and have room for a set - Its final print edition was in 2010, a 32-volume set.
*I understand Britanica has now started to provide some free content in some shape or form though probably "nothing free" for anglers...
[ame="http://en.wikipedia.org/wiki/Encyclop%C3%A6dia_Britannica_Online"]Encyclopædia Britannica Online - Wikipedia, the free encyclopedia[/ame]