There are a few reasons, but the main one is the same reason there was demand for beanie babies.
Crypto is only more complicated because it also has other groups, like anarchists/libertarians that see crypto as subversive to government, taxes, and regulation. They buy in out of a mistaken philosophical view that it furthers their political ends.
But the key factor is that they were they fed stories via a new information medium: The Internet. And the Internet is also where beanie babies could be bought (via ty.com) and resold (via Ebay). An argument could be made that Ebay might not even exist today without the beanie babies phenomenon which gave it early traction.