The Economist summarizes the opening of Martin Wolf’s, Fixing Global Finance, as follows:

Finance allows the creation of vast enterprises out of the combined capital, supplied at modest cost, of millions of people. It permits upstarts to launch companies, challenging the power of incumbents. It allows people to smooth their spending over a lifetime. It facilitates risk sharing and insurance. Empirical studies confirm that these advantages are real.

I take it those empirical studies did not take into account the current economic crisis wherein we are all benefiting from the facilitated risk sharing.
Yes, those vast enterprises, governments and large businesses, have done wonders: count the wars, count the environmental destruction, count the devastated indigenous peoples, notice the vast income and wealth discrepancies.

We do need a financial system but perhaps one that does not facilitate disasters.