“Most game ideas don’t come from the basement of Hasbro,” said Mr. Johnson, the BMO analyst. “A lot of the toy industry is very inventor driven, but games especially.”

Pie Face, for example, became one of Hasbro’s top-selling games in recent years after the company saw a viral video of the game and bought the distribution rights from an independent toymaker in Britain, Mr. Berkowitz said. “We really got to that market leader position by partnering with everybody in the world.”

And Mattel snapped up Escape Room in a Box after spotting it on Kickstarter. “We want to look under every nook and cranny,” said Ray Adler, Mattel’s global head of games.

Retailers are in on it, too. “We’ve always believed in emerging companies, individuals and artists,” said Gabrielle Conforti , the chief merchandising officer for Urban Outfitters, which sells Game Night in a Can.

Crowdfunding and 3-D printing “put everybody on the same level-playing field,” said Rena Nathanson , chief executive and co-founder of the game company Bananagrams. “It enables people with very limited budget to get prototypes made and seen.”

Board games do not require molding and other tooling needed for toys like action figures, which helps keep the manufacturing costs down for small businesses, Mr. Johnson said.

But the category is not without challenges. Most games imported to the United States are made in China, meaning the tariff war between the two countries is a big concern. President Trump said last month that the United States would increase taxes on all Chinese goods, including toys.