Even before the latest outbreak of gun violence on American streets -- the mass shooting over the weekend in Southern California -- major consumer brands were already facing pressure to stake out positions on gun control as part of a trend in which companies promote social causes along with their products.

Earlier this month, Chipotle Mexican Grill Inc. (NYSE:CMG) issued a statement asking customers to leave their guns at home. Starbucks (NYSE:SBUX) and Jack in the Box Inc. (NASDAQ:JACK) had previously asked patrons not to carry guns while dining. Analysts suggest such public stances could become a new normal, with major brands effectively shaping policies in reaction to changing public values.

“This move is all about how these companies want to position their brands,” said Nick Setyan, restaurant analyst at Wedbush Securities. “The overarching trend today is brand evolution towards a more sustainable planet, peaceful world.”

Starbucks, the world’s largest coffee retailer, has been one of the first to adopt a no-guns-on-the-premise stance.

“Few topics in America generate a more polarized and emotional debate than guns,” Starbucks CEO Howard Schultz wrote in an open letter Sept. 17, 2013.

“In recent months, Starbucks stores and our partners [employees] who work in our stores have been thrust unwillingly into the middle of this debate. That’s why I am writing today with a respectful request that customers no longer bring firearms into our stores or outdoor seating area,” he wrote.

On May 19 of this year Chipotle made a similar public statement asking customers not to bring guns into their locations. The declaration came soon after a group of rifle-toting gun rights activists gathered at a Chipotle in Texas.

“Recently, participants from an ‘open carry’ demonstration in Texas brought guns (including military-style assault rifles) into one of our restaurants, causing many of our customers anxiety and discomfort,” a company representative said, according to local news reports, adding a request that customers not bring guns into their restaurants.

Chipotle's experiences illustrates the complexity at issue for brands that operate across the United States: In some areas of the country, showing support for gun control can be a popular means of currying consumer favor, but in others it can place a brand at odds with local values.

In many states, people are allowed to carry firearms openly in public. The term “open carry” has become shorthand for a movement to increase visibility and awareness of this practice in places where it’s allowed. Advocates for the practice say it helps preserve their Second Amendment rights, and often gather at retail locations for demonstrations.

On one such occasion earlier this month, members of the advocacy group Open Carry Texas entered a Jack in the Box in Fort Worth with their assault rifles. It was enough to scare employees into the restaurant’s freezer until police arrived, and prompted yet another corporate anti-gun statement from the fast-food company.

“The presence of guns inside a restaurant could create an uncomfortable situation for our guests and employees and lead to unintended consequences,” a representative said, according to a press release.

The statement came just days after a group called Moms Demand Action for Gun Sense in America petitioned the company to take a stance on the issue after the incident.

The group, which formed after the mass slaughter of children at Sandy Hook Elementary School in Newtown, Connecticut, in December 2012, aims “to build support for common-sense gun reforms,” according to its website.  Members have successfully petitioned major companies including Starbucks and Chipotle, to publicly address gun issues.

“Laws continue to change at local and state levels, and businesses are becoming involuntary participants in the debate,” said Patrick Lenow, a spokesman for fast-food company Sonic Corp. (NASDAQ:SONC).

One of Sonic's locations was featured in a video that Mother Jones published Tuesday, depicting a group of seven or eight men who were carrying semi-automatic rifles getting kicked out of a Sonic Drive-Thru. Lenow said the company has historically relied on local gun laws to guide how employees address guns on the property, and is continually analyzing how the organization treats the issue.

In the clip, an employee tells the men he won’t serve them and will call the police. The men cancel their orders, leave the restaurant and linger in the parking lot discussing their situation. One man leads his young daughter to his car, rifle slung over his shoulder. Others debate waiting for the police, and other dining options.

“Man, we can’t do nothing,” the gun-toting man says as he filmed the video at Sonic.  “Nobody likes us.”