I think the result should be a net gain to society, as is generally the case when you make markets more efficient.

Taking power away from the most powerful actors is often good a net gain for society. That doesn't make it a "easy win".

Matt Taibbi writing about the municipal bond market is worth reading:

Along with virtually every major bank and finance company on Wall Street – not just GE, but J.P. Morgan Chase, Bank of America, UBS, Lehman Brothers, Bear Stearns, Wachovia and more – these three Wall Street wiseguys spent the past decade taking part in a breathtakingly broad scheme to skim billions of dollars from the coffers of cities and small towns across America. The banks achieved this gigantic rip-off by secretly colluding to rig the public bids on municipal bonds, a business worth $3.7 trillion.