You are wrong. When there is such a high demand mixed in with an easy way to reach a market (SBT/BSTs), it creates a opportunity that's like no other. Never in history has there been a medium like the internet to grow wealth or scale. One of the biggest barriers that most offline business have is setup, and scaling, then getting customers and clientele. Whether it's on wickedfire or BHW or Wafo, the demand is already there (or the audience at least). The operation is rather easy, they fill out a form, and wait for results. The hardest part would be execution on the sellers side. If they have a majority of that automated 50-90% then they've achieved what most offline businesses can only hope of achieving.
Remember, they are hyper-focused and selling a single service, which doesn't require a lot of overhead in the beginning, and even when scaling if it has been reduced to mostly automated work where a $10 VA can input some text and the order gets processed, that's a profitable operation. Offline businesses can only dream of such a thing. I think you are busy thinking about computers, offices, and employees and all that fun stuff of dealing with office politics.
A guy can literally be sitting in his home office, create a product, such as links, create the process of execution, setup an order form, and create a SBT/BST thread and start making sales. Now with any business there is always a chance for failure - especially if your product/services is shitty. But if you have a half decent product, and deliver on time, you've got an instant business that can be grown and improved within 24 hours. And if you fail? Just try again next week, since overhead is so LOW, it's impossible to not make money if you really have your shit together AND have a product people want/demand. Remember, there is no committee meetings, manager meetings, No TPS reports, no research and development phase and all that shit that gets in the way of making money; it's literally you with your ideas (and a programmer if you aren't one) versus the internet.
The internet strips away all the bullshit that people can come up with on why something failed, and gets it down to its root levels. Is there demand? Can I scale it? What is the competition like? And Is it profitable? I find the internet to be one of the purest forms of battle. It's you versus your ideas and the market. If you've got a great idea, and can get your shit together to come to market, and there is demand, there is nothing stopping you from succeeding except YOURSELF and your own limitations.
Another great thing about it BST that is taken for granted - INSTANT customer feedback. If you are screwing up, people will let you know, and you can improve that product/service almost instantly. Think about it, if I have a problem with Term Explorer, WordAi, or MicroSite Masters, I can instantly talk directly with the developers, owners, and operation and get my problem fixed. In what offline business is that instant communication even possible? Very few. That's another advantage being 100% web oriented has.
I've seen guys due 6 figures off of 2 BST threads. Another dude right now is at 5 figures in less than 5 days. What you are missing is that $30 BST from BHW didn't have a time limit. And if the demand is there, example SGW back in the day, people can become undercover millionaires off of a BST and no one but themselves know the profit margins.
If you are saying that it's impossible to scale a million dollar operation online, then you are pretty much saying it's impossible to do the same with affiliate marketing as well. The difference with affiliate marketing is you have to find the audience and entice them into coming to your site, landing page, and clicking the offer. Whereas a BST, the audience is already gathered in one spot for you to market to. That's a huge advantage most people don't consider.