Prediction markets, which allow individuals to wager on real-world events such as elections or flight delays, have seen a rapid increase in popularity, sparking debate over their role in financial decision-making. According to recent data, monthly global trading volume on major prediction-market platforms surged from under $5 billion in September 2025 to $23.8 billion by April 2026, surpassing legal sports betting volumes in the United States by about $10 billion monthly. This rise comes amid regulatory scrutiny, as the U.S. Securities and Exchange Commission is considering whether to approve exchange-traded funds (ETFs) linked to these markets.

Critics, including David Booth, founder and chair of Dimensional Fund Advisors, caution that prediction markets may pose significant risks to everyday investors. Booth compares these platforms to gambling and warns that they offer a false promise of prediction and profit, often resulting in losses for participants. The odds are frequently stacked against casual bettors due to the involvement of professional traders with extensive research resources, as well as the opaque nature of many products derived from these markets. This dynamic, Booth argues, creates an uneven playing field where insiders hold a distinct advantage, effectively “rigging” the system.

This growing enthusiasm for prediction markets reflects a broader cultural shift toward immediacy and the allure of quick financial gains. Booth highlights a survey by Betterment showing that more than a quarter of Generation Z respondents incorporate sports betting into their long-term financial strategies, while over half have rerouted investment funds to betting activities at least once. He suggests that this trend could undermine traditional investing principles that emphasize long-term growth and disciplined strategies.

Comparing prediction markets to established public financial markets, Booth underscores the differences in transparency, investor protections, and market efficiency. In conventional markets, buyers and sellers engage in voluntary transactions with adequate disclosure, fostering prices that reflect genuine economic value. Over time, this allows investors to benefit from economic progress without relying on the losses of others. In contrast, prediction markets’ reliance on wagering structure means one party’s gain corresponds directly to another’s loss, making sustained profits unlikely for most participants.

Booth further traces the evolution of financial knowledge, noting that past misconceptions about stock picking eventually gave way to a broader recognition of the benefits of diversified, low-cost portfolios and long-term investment horizons. He argues that the rise of prediction markets and related betting-like products threatens to reverse these gains by conflating gambling with investing.

While acknowledging the potential for recreational engagement, as exemplified by his personal experience gambling modestly in Las Vegas, Booth advises investors to avoid confusing speculation with true investing. He contends that sustainable wealth accumulation comes from supporting real economic progress driven by companies and individuals solving tangible problems, rather than attempting to predict uncertain futures through bets.

As regulators and investors grapple with the surge in prediction-market products, the debate continues over how, or if, these platforms should be integrated into the broader financial ecosystem, balanced against concerns about transparency, fairness, and long-term investor outcomes.