Failures in the former may cost their investors their investment, but it won't cost them more money than they've ever made, or put them into the red so deep as to destroy their whole industry, or bring down the global financial system. While both sides play the odds and spread their bets, the nature of risk and payoff is very different.
Also, startups represent an attempt at creating real wealth where none was before - combining labor, capital, innovation, and raw materials to make products that can be sold for more than the sum of their inputs, or services that save time. Alot of what caused the financial crisis was more akin to gambling, despite protestations of 'financial innovation' to the contrary. Failure in the former is admirable, the latter not so much.
http://www.youtube.com/watch?v=Odbul86485w
but it wanted me to sign in, and I wouldn't. (I don't have a youtube account and didn't want to use my goog)
The current fraud-ridden crisis has damaged both the economy and government much worse, but has only seen a few show-trials like Bernie Madoff. Moral Hazard is all but non-existent, Wall Street is laughing behind closed doors, the US Government is their mark/whale now.
Lawrence Lessig has a good TED talk linking problems like this and others to the influence of money and revolving doors in Washington:
http://www.fixcongressfirst.org/blog/entry/lawrence-lessigs-...
Edit: Direct link to the video - http://blip.tv/file/4266077