On Wednesday, online gaming firm Guild Esports announced plans for an initial public offering on the London Stock Exchange. The company is co-owned by former soccer player David Beckham, and will use the cash raised to recruit professionals to compete in popular games “Fortnite”, “Counter-Strike: Global Offensive”, “Rocket League” and “FIFA”. Grand View Research expects the booming business of videogame competitions to be worth $6.8 billion in 2027, up from $1.5 billion today.

But investors beware: Sports clubs tend to be terrible companies to own. Players have outsize power to negotiate pay—in the profitable English Premier League, wage bills are above 60% of clubs’ revenues—and can often bypass employers through sponsorship deals. Manchester United has given investors a return of just 25% since floating on the New York Stock Exchange in 2012, compared with 181% for the S&P 500.

Mr. Beckham’s experience as a successful soccer player—and even more successful object of sponsorship—should have taught him a lesson worthy of Karl Marx: In elite sports, labor almost always trumps capital. Taking the class war to an online “battle royal” shouldn’t yield a different outcome.

Write to Jon Sindreu at jon.sindreu@wsj.com