After several days of active discussions, REI said it learned that Vista did not plan to make a public statement, outlining a clear plan of action. “As a result, we have decided to place a hold on future orders of products that Vista sells through REI while we assess how Vista proceeds,” the company said. “Companies are showing they can contribute if they are willing to lead. We encourage Vista to do just that.”

Vista did not respond to an email seeking comment and has not issued any public response to the decision by the retailers. But one of its brands, CamelBak, tried to distance itself from Vista’s gun selling operation, arguing in a statement that it was an “incorrect assumption that the purchase of any of our products may support a cause that does not fit the mission/values of our brand.”

CamelBak, founded in 1989, is popular with athletes for its packs that allow athletes to hydrate without using their hands as well as its brightly colored water bottles. It was acquired by Vista in 2015 for $412 million. “Our brand falls within the Outdoor Products segment of our company, which operates separately from Vista Outdoor’s Shooting Sports segment,” the company said in a statement. That segment manufacturers a variety of guns, including AR-15-style rifles.

On social media, some argued that boycotting brands like CamelBak and Giro would only hurt people making quality products. Others chided REI for what they saw as mixing business with politics.

But retailers are being forced to respond to the growing call to arms that is racing across the internet. On Twitter and Facebook, lists and petitions are being widely circulated of myriad companies associated with the gun lobby or brands owned by gun manufacturers, urging customers to boycott and retailers to drop them.

“I only discovered a week ago that my children’s CamelBak water bottles and the Bushnell binoculars that I bought for my 10-year-old who is into birding were associated not only with the gun lobby, but with companies that manufactured assault weapons,” said Sarah Latha, a 39-year-old mother of three who works for the provincial government in Ontario. “It was incredibly disturbing.”

On Sunday evening, Ms. Latha put up a petition on change.org demanding that Mountain Equipment stop selling brands owned by Vista Outdoor. It quickly drew more than 50,000 signatures.