Making ETS pay for itself - It's a difficult question.
Virtually every site owner is fighting to answer the question of how to pay for the site and time spent maintaining it. By tradition web surfers are not willing to pay for anything directly. This is made worse by the fact that most first-time visitors are arriving by way of a search engine. Limiting and controlling content, establishing a two-tier membership, isn't compatible with this.
Advertising is a popular route to income but association with any particular product or manufacturer greatly increases management burdens and often conflicts with fair reviews, open opinion, presentation of all the options. Manufacturers with higher profit margins, those most likely to advertise, tend to be making higher end products. How do you square the circle of having to cater to a manufacturer while telling people the honest fact that the product just isn't all that.
Then again there are survival, preparedness, often quasi-military sites that cater to manufacturers. They seem to drift into gear fetishism and cease to function as reliable information sources and living community. I have been told many times, often in no uncertain terms, that it is simply impossible to survive without gear that costs less than some arbitrary figure.
Developing a two-tier system of membership is a popular strategy but one that seldom seems to work out. If the site was about art or specialized content it might work. People will sometimes pay for exceptionally valuable information or content. Particularly if the information allows you to make money. Several financial sites do this but content value, particularly in the light of the latest failures, is all over the place and results are highly variable. I'm somewhat surprised many of the financial websites and newsletters still exist.
A two-tier system of survival information is pretty hard to maintain. Pretty much all the basics are open source and just a well worded Google search away. From what I have seen the 'member content' of most of the pay sites, those that are still available and updated regularly, is pretty weak. In one case I'm familiar with the site just copied material lists off a public LDS site.
Then again many of those lists were just tarted up versions of USG/USDA materials. Which were lifted from various other sources. You can look up supply lists that go back to the Shackelton expeditions and Lois and Clark and a see a lot of commonalities. The requirements for food, water and shelter haven't changed in a few thousand years. As far as I can tell there is no inside information.
The one thing that a good survival forum has to offer is interaction, input, interpretation of events past and present, encouragement, and a community to bounce ideas off of. But a two-tier system doesn't tend to encourage any of this. If anything it tends to work against community by setting up claques, experts and insiders.
Even the idea of identity is not without issues. I post under a pseudonym in part because I think that who I am is irrelevant. I want my words to stand on their own. If they are useful and reasonable then make what you will of them. If not then ignore them. There is no point to setting up a system of authority or expertise. The history of survival situations is ripe with experts who fell and rank amateurs who made it through. There is also the matter of whether it is better to listen to people who constantly find themselves in survival situations or people who simply avoid them.