well I'm sorry, but that also applies to VC/angel funded startups game nowadays, which Cuban participates in.
Has it not become painfully clear that the financial system has come to dominate the economy to a greater extent than the value it provides? http://en.wikipedia.org/wiki/File:NYUGDPFinancialShare.jpg And that this has been driven by the interests of those who profit personally from such a configuration, in opposition to the interests of society as a whole? http://www.thisamericanlife.org/radio-archives/episode/405/i.... I'd say those statements are hardly controversial to anyone without a vested interest in the status quo.
I grant that "hedging risk" and that other standby, "ensuring liquidity", do have value, just not to justify the existing system. The liquidity argument in particular comes off as ironic in light of the fact that trillions of public dollars provided to the financial sector in the name of opening liquidity to the general economy did no such thing.
In any case, since you feel the financial sector is too large, what do you believe is the proper size of the financial sector?
To turn to your other point, I certainly respect what you're saying, but once again there's this problem of reductio ad absurdum: forces leading straight to financial meltdown can hardly be representative of a proper system. What you're saying sounds dangerously close to "the system worked". Or perhaps, "the system just didn't follow its own logic consistently enough".