Avon et al are the people at the top of the pyramid. They don't go out of business, they keep running the scam until they get arrested or run out of suckers. And P.T. Barnum said something about the latter.
It's the suckers whose "investment" in one of these things goes to zero, which happens all the time.
There are cryptocurrencies that go to zero, but there are also government currencies that go to zero. They go to zero when people stop using them as a currency, not when they become so widespread that you've saturated the market for suckers.
Ah, I misunderstood. Touché, that is a fair distinction. It's hard to know how widespread leverage is used in crypto investments. One of the scary things about cryptocurrency investments is the lack of regulation, letting unsophisticated "investors" easily take on ludicrous amounts of risk. It's not uncommon to see 100x leverage offerings at crypto exchanges [1][2][3]. If used, it obviously can result in "investment goes to zero"—or worse—situations.
I feel like people should be made aware of the risks and if they haven't misled you about what's at stake, you're an adult and you can place your bets.
That isn't a scam, it's a gamble. It's the same as going to a brokerage and selling short, or buying a piece of land sight unseen. They are not allowed to lie to you. You are allowed to be an idiot and lose all your money.
It's the suckers whose "investment" in one of these things goes to zero, which happens all the time.
There are cryptocurrencies that go to zero, but there are also government currencies that go to zero. They go to zero when people stop using them as a currency, not when they become so widespread that you've saturated the market for suckers.