Charles Schwab, E*Trade, and TD Ameritrade have seen a combined $18 billion in market value erased a

Large brokerage stocks have taken a hit since the price wars escalated Monday, with several major players cutting fees on stock and exchange-traded fund transactions to zero. Charles Schwab has lost $8.5 billion in market value since Monday, while E*Trade has shed $2 billion and TD Ameritrade has seen $7.5 billion erased over the same period.  Cutting fees on trades to zero eliminates revenue streams for the traditional brokerages.  Read more on Business Insider. Brokerage stocks are...