Legendary investor Charlie Munger continued a war of words Thursday with popular online brokerage Robinhood Markets Inc. over the way it and others have enabled and profited from the recent boom of individual investing.

“I hate this luring of people into engaging in speculative orgies,” Mr. Munger told The Wall Street Journal from his Los Angeles home. Robinhood “may call it investing, but that’s all bullshit.”

He added, “It’s really just wild speculation, like casino gambling or racetrack betting. There’s a long history of destructive capitalism, these trading orgies whooped up by the people who profit from them.”

Mr. Munger, 97 years old, is the vice chairman of Berkshire Hathaway Inc. and Warren Buffett’s longtime business partner. His comments Thursday echoed criticisms he lobbed at Robinhood the day before.