Some of them invest in infrastructure and building the whole ecosystem, they dont just buy x amount for x dollars hoping it will go up x2. For example, look at Barry Silbert and DC Group.
Indeed the best thing is to invest in blockchain as a technology and help build and pioneer in this new field. Opens such a vast opportunity for new business ideas. I'd think smart wealthy people in the IT industry do both. At least let's hope they do as this adoption could benefit the whole system greatly.