"Anytime you take a stand on an issue you will polarize some part of the marketplace," said Allen Adamson, chairman of brand-consulting firm Landor.
The support from some of the country's largest companies raised the ire of some conservatives who threatened to take their business elsewhere.
After Southwest tweeted "#SouthwestHeart beats for love," with the hashtags "MarriageEquality" and "LoveWins," David Lane, founder of the American Renewal Project, threatened to do just that.
"If Southwest Airlines wants to get embroiled in the cultural battle over same -sex marriage - and alienate 50 percent or so of your customers - this tweet is a good way to do that," Lane wrote to Southwest in an e-mail he provided to The Washington Post.
"I think the businesses that are doing this are very shortsighted," he said later in an interview. "I think the only way they walk this back is if there's pain involved."
Southwest, which didn't return requests for comment, operates hubs in the South and Midwest, regions where support for gay marriage is the lowest in the country.
The question for these companies, analysts said, is who do you want to upset? Saying nothing will land businesses in the doghouse with young consumers who want companies to be corporate citizens, not just salesmen, Adamson said. But alienating conservatives comes with its own risks.
Corporations need to build their own identities beyond their product, he said. Those tactics traditionally were reserved for issues where the country's opinion was united, like during times of war or after natural disasters.
Now, if businesses don't say something, consumers - especially millennials, a demographic companies are desperate to make brand-loyal - are likely to walk away.
"If a company doesn't stand up, customers will vote with their wallet and go elsewhere," Adamson said. "And it's not because there's better coffee or jeans or airplanes."
Levi Strauss & Co. has a history of speaking out on social issues, including being an advocate for HIV/AIDS education, and has not shied away from weighing in on gay marriage.
It was the first company to file a friend of the court brief when the California Supreme Court debated same-sex marriage in 2007. Today, it sent out multiple posts on Twitter in support of the decision and featured a rainbow-themed logo.
"Consumers care about value and they also care about values," said Anna Walker, Levi's senior director of public policy and advocacy.
