They're putting everyone at risk.
As others in this thread have pointed out what these VCs do is make wildly risky gambles. When it pays off they make billions of dollars in profit and congratulate themselves for their foresight and the power of capitalism. When it doesn't they go cap-in-hand to the federal government, saying that if they're allowed to collapse it'll destabilize the entire economy.
If it were just some rich billionaires who might have to sell their second private jet when this collapses I'd agree with you: who cares what they do with their own money. But what's going to happen is that the taxpayer will end up footing the bill for their reckless behavior, and millions of people will end up worse off for it as governments cut back on welfare, healthcare, and aid programs to balance the books. In a very real sense, people are going to be paying for VC greed with their lives.