Gay rights activists kissed at Chick-fil-A stores across the US, just days after the company set a sales record when customers flocked to the restaurants to show support for the fast-food chain president's opposition to gay marriage.

The duelling displays of activism this week demonstrated an unusual amount of staying power over a flap that erupted weeks ago. The prolonged controversy speaks to underlying regional tensions in the US that transcend the issue of gay rights.

Coursing throughout the conversations on social media, in letters to the editor and in long lines to buy chicken sandwiches is the sense among proud Southerners that the outcry over Chick-fil-A president Dan Cathy's comments smacks of regional stereotyping. When public officials in Boston, Philadelphia and Chicago tell a Southern icon such as Chick-fil-A that it's no longer welcome, and that Cathy should keep his opinions to himself, many in the Atlanta-based chain's home region hear more than a little northern condescension.

"Maybe the reaction is just because we're Southerners," said Rose Mason, who was lunching at a Chick-fil-A in suburban Atlanta yesterday (local time).

Mason, who described herself as Christian, said she grew up in New York City. Now, she said: "I deal with my sister telling me we're a little backward. People have this idea that we're just behind on everything. So they view anything we say through that (perception)."

Cathy, a devout Southern Baptist whose family has always been outspoken about its faith, sparked the controversy by telling the Baptist Press that he and his family-owned restaurant chain are "guilty as charged" for openly - and financially - supporting groups that advocate for "the biblical definition of a family unit". He later added that the United States is "inviting God's judgment on our nation when we shake our fist at him and say, 'we know better than you as to what constitutes a marriage’."

For Marci Alt, organiser of the protest at a Chick-fil-A in the relatively liberal Atlanta suburb of Decatur, it's Cathy's financial backing of conservative groups such as the Family Research Council that takes the conversation beyond merely what he said.

Alt said Cathy has a constitutional right to speak out against same-sex marriage.

"But when he puts a pen to paper and writes a check to an organisation that is about to squash my equal rights, I have a problem with that."

Cathy's comments were in keeping with the tradition established by his father, Truett Cathy, who started the chain in 1967 and never allowed franchises to open on Sundays.

Beyond Friday's organised displays of affection, there were other signs that the furor still had legs. Police were investigating graffiti on the side of a Chick-fil-A restaurant in Torrance, California, that read "tastes like hate" and had a painting of a cow, in reference to the chain's ubiquitous ads featuring cows encouraging people to eat poultry.

In Tucson, Arizona, an executive at a medical manufacturing company lost his job after filming himself verbally attacking a Chick-fil-A employee and posting the video online.

For William Klaus, a 26-year-old X-ray technician with traditional views on marriage, the debate starts at and ends with Cathy's liberty to voice his beliefs.

"He said what he said. Freedom of speech. Bottom line," Klaus said at a Chick-fil-A in Jackson, Mississippi.

However, that goes for Cathy's critics, too, said Klaus, adding that he stopped by the Jackson store simply to pick up some good food.

"For someone to blast him for his opinion, so be it - they have that right."

- AP