The first time something happens is chance, they say; the second time is coincidence. 

The third time? That's a pattern.

So what about the fourth time? In the case of Waffle House, that's a boycott.

At least, it will be if people follow the lead of people like the daughter of the late Rev. Martin Luther King Jr., and other activists.

"Family, let's stay out of @WaffleHouse," Beatrice A. King, CEO of the King Center, wrote on Twitter, "until the corporate office legitimately and seriously commits to 1) discussion on racism, 2) employee training, and 3) other plans to change; and until they start to implement changes."

The call to action stems from at least four recent racially-tinged alleged incidents:

1. The first incident, of course, was the mass shooting at an Antioch, Tennessee Waffle House, April 23, in which a gunman killed four young people of color before being stopped by an unarmed customer.

2. Oddly, at almost the exact same time as the shooting, a black woman in a Waffle House in Saraland, Alabama, 400 miles to the south, was tackled by police who "placed a hand on her throat and exposed her breasts," and at one point threatened to break her arm.

3. Four days later, a black customer said she was locked outside of a Waffle House in Pinson, Alabama, while the restaurant continued to serve white customers. 

4. Most recently, on May 5, viral video shows a Warsaw, N.C. police officer choking and slamming a 22-year-old black man who was at a Waffle House after taking his 16 year-old-sister to her high school prom.

"I wish people would not blow things out of proportion and not let one situation create any additional situations," Warsaw Police Chief Eric Southerland told a newspaper.

But King is by no means alone in drawing a line from one incident to another, and asking people to boycott the 1,800-store chain, which is privately held and concentrated in the South.

The head of the NAACP Legal Defense and Education Fund released a statement:

"We're once again outraged by a video showing police officers using excessive force on an unarmed, non-violent African-American Waffle House customer. Once again this incident was sparked when a Waffle House employee called the police after the patron allegedly complained about customer service. And once again the police responded with violence."

And the influential activist Shaun King tweeted that he was "done" with the chain.

I tried without success to get a comment from Waffle House. I also can't find any statement from them so far about the most recent incident.

However, they defended employees who called police in Saraland, and as the New York Times reported, these kinds of allegations are not exactly new:

Waffle House ... has also faced multiple lawsuits from customers complaining about racist treatment from employees.

Some plaintiffs said that restaurant workers used racial epithets and ignored black guests while catering to white customers, and the chain's restaurants have tangled several times with the Equal Employment Opportunity Commission, which serves as a discrimination watchdog.

The company has long rejected allegations of racial bias, and its laminated menus used to offer a more wholesome version of history than the one critics raise: "America's Place to Work, America's Place to Eat."

What's different now, however? Of course, it's partly that everyone has a camera and access to social media.

But there's also palpable progress in the national tolerance level: people just aren't as willing to do business with brands that treat customers this way as they once might have been--especially minority customers.

That's why you see companies like Starbucks and Nordstrom Rack moving very quickly now to apologize after incidents in which their employees called the police on black customers.  

And it's why Waffle House will have a very steep hill to climb, if these calls for boycotts take hold.