Like, Why would the Fed buy futures when they can buy stocks today?
In addition to all of the above given reasons, I repeat what I said this weekend. (The following comments are for a normal business, and I believe that the CFTC exempts the major market players from even the standard margin requirements for individuals and other businesses.)
1. The accounting treatment for Futures and stocks are vastly different. The nominal value of futures do not appear on most financials.
2. The amount of money needed (assuming that the Fed would have to have margin, which I think is not a good assumption) is vastly different. The margin tied up or encumbered for a future is a much, much smaller percentage of the nominal value of the amount controlled versus stocks.
3. For stocks they would have to pay "money" to buy. For a future, only existing funds are encumbered (at worst) and no actual money changes hands when the future contract is purchased or sold.
If the Fed or any other business entity bought a future contract, I am not sure where the nominal value of the future contract would appear on any financial statement. I think only the mark-to-market change would appear at the close of the accounting period.
Finally, the purchase of stocks leaves footprints or fingerprints (shows and can be traced on financials for example). On the other hand, the purchase of futures leaves few fingerprints or footprints for tracing purposes.
These are the mechanics of the system that I struggle to understand and would sincerely appreciate any corrections if I am wrong in my analysis/reasoning.