>http://www.wired.com/business/2012/08/ff_wallstreet_trading/all/

Buying stock of a company was a matter of trust - one bought because of believing that it will be prosperous, and sort of joined in (as in voting with the wallet) for some foreseeable future.

Now they wholeheartedly trust each other for a few milliseconds, few hundred times a day.

I don't see what service are they doing to the civilization, apart from taking everybody's excess money.