Because that entails hard work.
A lot of the marketing behind these scams is that they're different than everything you've tried before - the point being is that the number of people who fall for these scams isn't enormous, but they will fall for scams over and over again. Just probably not from the same person selling it.
It's the same as any kind of cult messaging. It's not surprising that the size of a cult designed to exploit people has an upper limit, but it is shocking that the same people will join multiple cults time after time.
(I do know at least two real exampless of this meta-approach to scamming: 1. there are meta content-farms, which hire people and train them to run seemingly-independent content-farm YouTube / TikTok / etc channels; and 2. there are serial Kickstarter/IndieGogo scammers, that follow a loop of forming a new shell company, hiring a new actor to pitch a fake idea, steal people's money for it, and disappearing.)
And, while they're at it, why not constantly seek to acquire the pitch+content from smaller, nascent money-making course creators, and run their content through your existing business engine? Why not be the EA of scams?
It takes capital, time, and work to become “the EA of scams”, at which point you’re calling further scrutiny on yourself, meaning even more work (and staff, who you’ll have to trust) to not be in hot water with the law.
Scammers, like the people they scam, are mostly after a quick easy buck. You’re posing “why not” questions as if it’s straightforward to accomplish what you’re suggesting. It’s not. It takes effort and risk without a guarantee of success. Most scammers don’t become “the EA of scams” for the same reasons most game companies don’t become EA.
An important feature of these scams is to frame success and failure as being entirely in your hands: it’s not the system’s fault that you didn’t achieve success, it’s yours and yours alone, you didn’t want it bad enough. Someone who falls in that hole is bound to do it again, this time for a different grift which looks easier. They’ll do as much as it takes until they strike gold, go bankrupt, or finally understand it’s all a scam. That last one can take a long time to come.
In sum, money making courses don’t need an infinite supply of new chumps when they can keep reeling in the same ones. Offer some discounts and rewards for bringing in new members, and you’ve gone full MLM².
¹ https://en.wikipedia.org/wiki/There%27s_a_sucker_born_every_...
² https://en.wikipedia.org/wiki/Multi-level_marketing