"Their cut in just spread/commissions are 0.3% of the total $ traded volume." So in your opinion "they" average $300 out of every 100K trade on just their split on spreads or commissions? Please, at least apply some common sense before you start typing something on an internet bulletin board, even in this degenerated forum section..
Below is a snapshot of the last 24 hours of traded volume for GAIN FX pairs and CME Currency Futures. Gain Volume Volume CME AUD/USD 33758 42822 6AZ9 GBP/USD 61778 49096 6BZ9 USD/CAD 38169 35350 6CZ9 EUR/USD 43229 119705 6EZ9 USD/JPY 42823 49714 6JZ9 USD/CHF 51130 25492 6SZ9 For CME futures: Brokers charge commission and exchange fees of approximately $4 - $6. Gain charges no commissions but makes a spread which varies by instrument and market conditions. The point trying to be made is the FX dealer network earns a min $ on the total traded volume. Just a low ball guestimate: $30 x 270887 transactions = a minimum of $8,126,610 gross to operate from. Counter Party trading activity adds substantially to the broker's bottom line.