Futures are a zero-sum market. Nothing is created out of nowhere. What you win must come from somewhere. And in the financial markets in general, there is a shift, a transfer in wealth going on all the time. I did not call it stealing. But it is a huge, global game. And in such a game, there are not many winners. There are very few who win big consistenly over a long period of time. That money, the gains of the few, they come, among others, from the many who are losing. Thats a general principle in life, it is a law of nature (Gaussian/ normal distribution): the top of the mountain can never be a crowded place.
Not everyone participating in the futures market are looking to make a profit per se. Remember that the primary function of the futures market is to hedge and control risk from your other positions. Speculation is secondary.
As long as there is liquidity, you're not really competing against anyone.