Capitalism and people getting rich is for better or worse exactly the stabilizing factor that has lead to the success of the modern world we take for granted. Capitalism is the worst except for all the others.
I empathize that it appears the case it's not an optimal allocation, but to say you know it's a misallocation leans overly simplistic.
What you see as misdirection of resources is the product of competitive market forces that drive innovation and efficiency. And the market often finds value in ways not immediately apparent.
Is less efficient resource arbitration (futures, forex) worth the trade-off? Producers can make their own market and set their own prices. But do that in an information vacuum and there will be increased deadweight loss in the form of higher bid-ask spreads, increasing costs, reducing economic activity.
There are more benefits in the form of reducing volatility and increasing liquidity.
It is not at all as obvious as you make it that society would be better off had HFTs and similarly received sorts of "financialization" not exist.
