[1]http://en.wikipedia.org/wiki/Article_spinning [2]http://thebestspinner.com/
I don't know how either one works well, but I saw some similarities, and with my limited knowledge of how that name generator format works I would know either more or less about how article spinning works.
Imagine a 100$ tool that might return 0 to 200$, the tool author sells the dream, and collects a more reliable income.
You may see software like TheBestSpinner, XRumer and another one I can't remember the name of, basically a Wordpress comment spammer cannon that sell thousands of copies, more than that person would make using these tools themselves.
Of course, your $100 price might be a figure pulled out of thin air, not an accurate one.
So, either your cheap tool works and spam gets worse or it fails and people just use more expensive options.
PS: Spam is a billion dollar industry and plenty of people with fairly deep pockets.
That said, these blackhat forums tend to be full of people with little money. Many users are from places like India and Pakistan, trying whatever they can to eke out an existence. Since almost none of the users on those forums have money to buy the tools (even $100 is a very high price point for products on these forums), writing tools for them is a fool's errand.