It may seem like a funny example of the ways the wealthiest one-hundredth of 1 percent live. But it is also, as it happens, an uncommonly clear window into some of the deeper flaws of 21st-century finance.

Why do we have a financial industry? Banks, bond and stock markets, hedge funds and private equity shops play a lot of roles in the economy, but the most fundamental is to channel capital to its highest and most productive use. That’s a really important role, on which economic growth depends. When it is done wrong (as when the financial system funneled billions to money-burning dot-coms in the late 1990s or toward unsupportable mortgage loans in the mid-2000s), the consequences are devastating. When the financial system channels money to companies with good business prospects, making capital available to those with the best ideas, it works for everybody.

There are arms of the financial industry that don’t immediately seem to fit that classification of “people who help steer capital to productive uses” but that do make the whole system work better. For example, in futures markets there are traders whom you might want to write off as speculators, but in fact provide a useful service. They ensure that when an airline needs to insure against rising jet fuel prices, or a manufacturer wants to avoid the risk of being paid in a falling currency, somebody will be willing to take the other side of that trade at a reasonable price.

But at some point you get to parts of the financial industry that aren’t making the economy more efficient. There you find the people exploiting momentary inefficiencies to get richer without making the rest of us any better off. High-frequency trading algorithms are a prime example, with enormous computing power deployed toward exploiting split-second moves that have no meaningful benefit for a company that uses the stock market to raise capital or a long-term investor who wants to buy that stock.