Well I'm not sure if some of rich people do invest here in bitcoin cryptocurrency they make their owned business as well to make more money, perhaps peoples do invest here in cryptocurrency that was hiding their money to the government because we quietly store our money bitcoin from wallet with out any evaluation of money.
It ain't necessary for them to create their own business as well in btc for them to invest to it. Having a mining farm of their own is enough rather than creating their own business. I am sure that those rich bastards somehow invested on btc in secret and most of them are part of the so called whales who owns large amounts of btc. They don't necessarily hide their money with the government but rather they just do it in order to gain more.