Who knows? The rate of return is so high。
Rich people have resources we usually don't have. They can easily get into something or invest on anything and the legalities are not in their personal name but on holdings they have. There are those who are avoiding the media so they bought Bitcoin secretly. There is a big possibility that Warren is already into Bitcoin and other coins in the market.
Exactly! If I am a millionaire and want to multiply my fortunes thru Bitcoin then I would do it secretly since aside that there is no real good effect for them which most likely it will lead to either put tax on the large money I had invested or they come up an idea that as if I am evading paying tax. If we weigh the advantages of the public to know then I say that it wpuld be better for them not to know for your own sake.
Probably they already bought it some 2 or 3 years ago. I doubt that they just heard it only now or just in the past years. For me i think that is the reason why btc has reached this price. Because many rich people had invested in btc. Heck they can even have there own infrastructure just for mining. As long as there are any oppurtunities that these guys will get rich, they would take chances to have it. Probably satoshi even sold some btc in the early years and thats how it even became famous.