Pure profit! A mere investment of 100 billion federal coins, and if they close now, deducting the cost of the initial 100 billion, the bank's profit will reach the terrifying amount of 280 billion federal coins! All within less than a week! What kind of wealth accumulation speed is that?
Furthermore, what made these top financiers suspicious was that banks rarely deal in futures, and when they do, they play it safe with stable and profitable options like gold, which have less volatility and are closely tied to the banking industry, allowing them to control the prices.
And they won't hold too much, using just over a hundred billion federal coins, often closing after making several billion federal coins. They would never touch something like oil futures. In fact, most banks don't dabble in these futures, contrary to the general perception that banks are invincible.