Let’s take HFT for example. HFT firms are the reason that Mom and Pop investors can get efficient execution on the public markets. Compared to the inefficient markets that existed before, they have generated many many billions of dollars to pension funds, mutual funds, and individual investors.
I don’t think it’s possible to overestimate the positive effect efficient markets have had on everyone’s lives, from the richest to the poorest.
The world isn’t a zero-sum game, and markets aren’t either, everyone profits from a good free market.
To be candid, I'm fully on the same page as you: what's going on here is no different than what a really good pit trader did from 1800's -> 2000. It's just the digital, semi-invisible version, and because volumes are so large, the money is exponentially larger as well.
But, that's not all the HFTs get up to; a lot of it doesn't hit public markets, or isn't particularly helping w/ efficiency.
In regards to money, I think that decimalization actually really hurt market makers. There has been massive consolidation in the HFT space with most players either going out of business or being acquired. Profits are way down and latency arbitrage is almost impossible nowadays without billions of dollars of trading infrastructure. Profits have dropped by something like 90% in the last 10 years and the super-normal profits now (after consolidation) are just "normal."
The good thing about HFT is that with the right infrastructure, it's (almost) risk-free. The problem with HFT is that the returns don't compound, there's only a fixed amount of pennies that can be vacuumed up. This is in contrast with other non-HFT quant strategies, which can run tens or even sometimes hundreds of billions of dollars in capital and can make over 10% annually.
The story with HFT is the story with any new market. Players get in, make a ton of money. More players get in, now they are making a little less money. Even more get in, and now they aren't making enough money. Then the people not making enough get bought up or go out of business. And now the equilibrium has been reached: everyone is making "normal" money and everybody forgets about them.
And all of this is good, it's the natural market cycle. People like Elizabeth Warren were talking about how unfair HFT was blah blah, but now, no one cares. Fortunately, the entire cycle resolved before the government could get their sticky little fingers on it.
Just to be clear, I mostly think that's fine and whatever, who cares, but there has been a lot of deception in the space.
I could respond by explaining that HFT facilitates liquidity and price discovery, making trading cheaper overall. I could also counter that adtech isn't any better than fintech, or that it's a fallacy to suppose every intelligent person needs to maximize their ethical production in a capitalist society.
But I'm not going to engage in any of those rebuttals. Instead, why don't you take a look at the massive charitable work bankrolled and empowered by James Simons and David Shaw? Take a moment to read through the organizational mandates and scope of research for the Simons Foundation and DE Shaw Research (DESRES). These two men have poured billions of dollars from their personal wealth into making the world a better place in a variety of ways. Both of them explicitly cite cancer research as a core focus - what do you consider more ethical than that?
While we're at it, let's circle back to your specific example. You're talking about sending rockets into space - that's great! I bet you're a fan of Elon Musk and SpaceX then? Are you aware that Elon Musk made his first fortune through PayPal? Do you consider payment processing to be a virtuous industry? Was Musk maximizing his ethical potential by working on PayPal?
People (both on HN and at large) seem to believe that HFT is somehow unfair, probably because of Flash Boys or some uninformed NYT article.
But back to the point, unless you believe in communism, then the best way to help the world and add value is to make money. Simply put, if you are making money, you are doing good (there are exceptions, of course and they usually involve the government). It is folly to measure social contribution in any other way (charity isn't doing good, it means whoever you are giving it to is doing good).
People, especially with HFT, think the world and the markets are a zero-sum game. I think the problem people have with HFT is that it doesn't seem "fair." Mom and Pop don't have a co-located server with ASICs churning out latency arb trades so they shouldn't be able to do that either! But why would you expect Mom and Pop to be able to compete in the first place? They probably wouldn't be able to compete with dentists, race car drivers, or scientists, so why should they be able to compete with professional investors?