The U.S. fast food burger chain, Wendy’s, thought it had outsmarted the farm workers who pick their tomatoes in Florida, but their plan has backfired, with the revelation that their Mexican supplier was investigated for running a farm that kept men, women, and children as virtual slaves.

About a week ago, the Coalition of Immokalee Workers (CIW) finished a long 10-day march to cities down the U.S. East Coast to bring attention to conditions in the tomato fields and to announce a boycott of Wendy’s, which had refused to agree to the CIW’s Fair Food Program, which brings a 1-cent-per-pound increase in pay for harvesting the tomatoes. (Note: The Mexican source of Wendy’s tomatoes had not been reported in the press before last week’s column.)

Wendy’s CEO and hierarchy thought they could avoid involvement in the modest pay raise by switching suppliers, from Florida to Mexico. But a recent article in Harper’s magazine reported that Bioparques, Wendy’s Mexican supplier, had been investigated by Mexican federal labor officials for abuse of its workers, most of whom were kept inside the compound, fed poorly, and provided no schooling for the children.

A penny a pound doesn’t sound like much…and it isn’t. But Wendy’s apparently saw it as an unbearable burden for the giant corporations and looked for ways to get out of paying that extra penny. The nation’s other fast food outlets and some other regional and national food companies agreed to pay the extra one cent, simply because it did not raise the retail price of tomatoes and it does not raise the price of a burger with a slice of tomato in the fast food industry.

The CIW is a farm worker-run organization that, for years, has fought for better wages, improved and healthy working conditions, and the things that are needed to make for a sanitary and healthy workplace, such as fresh water and toilets in the fields and a place for hand washing. The extra penny per pound makes a big difference in the lives of workers who are at the bottom of the wage scale among American workers. With that extra penny per pound, they can afford better food for the children and try to find better housing for their families.

The public relations department of Wendy’s went into high gear, when CIW pointed out that the company was not willing to participate in the Fair Food Program, saying that there was no need, because they were not buying tomatoes from Florida. Wendy’s officials obviously did not investigate conditions at Bioparques’ sprawling tomato fields or they just did not care about working conditions. When the company said it did not buy Florida tomatoes, that left just two other places for their supply of tomatoes, Canada or Mexico. The Canadian tomatoes cost upwards of three times the other tomatoes, so it was clear where their tomatoes came from, Mexico.

It’s not as if the burger chain could not have easily discovered the conditions in the Bioparques operation, because the Los Angeles Times ran a series on the grower and the working conditions in 2014. The paper reported that, after a raid in 2013, 275 workers were freed from Bioparques, after which conditions did change somewhat. Some of the changes even satisfied Mexican labor law. However, a year-and-a-half after the raid by Mexican authorities, the case against officials of Bioparques was still not adjudicated and the fines imposed had not been paid, according to the paper. And, two company officials who had been charged with human trafficking were exonerated by a judge.

The operation in question, in Jalisco State, is one of two owned by the same company. The paper reported that “Bioparques is emblematic of Mexico's agricultural miracle. Its owner, Eduardo De La Vega, has transformed the region around San Gabriel, south of Guadalajara, into an export powerhouse with 500 acres of greenhouses, a packing plant and an executive airstrip.” The paper further reported that the company has sent as many as 6 million boxes of tomatoes a year to the U.S.

The following is how the Los Angeles Times described the action by Mexican officials:

“On June 10, 2013, three people managed to escape. They hitchhiked 100 miles to Guadalajara, where they notified authorities. The next day, dozens of state and federal officials arrived at Bioparques. Ricardo Martinez, who had resorted to rummaging through garbage cans for food, broke down when he saw police and soldiers pouring through the gates. ‘To tell you the truth, I cried.... Everybody there was really sick,’ he said. ‘They treated us like slaves.’ Two hundred seventy-five people had been trapped in the camp, including two dozen malnourished children.”

The CIW made its 10-day march, which ended last week in Palm Beach, Florida, to bring attention to its efforts to improve the working conditions, pay, and the lives of its members. They picked Palm Beach because it is the vacation home of Wendy’s chairman of the board, Nelson Peltz. If Peltz was ignorant of the working conditions at Bioparques, after Harper’s report last week, he should know, although he should have known as far back as 2013, when the L.A. Times ran its series on farm workers’ conditions across Mexico.

Rather Peltz and Wendy’s corporate bosses were willing to save that 1-cent per pound on the backs of the men, women, and children who were in the camp to serve the growers. These are the very conditions that farm workers in the U.S. have been fighting to change since the 1930s. Some progress has been made, but farm workers in the U.S., in general, have a long way to go to gain the respect, working conditions, and compensation they deserve. In the process, the CIW is exposing the underbelly of a corporation such as Wendy’s, which ignores the atrocious conditions that exist in the fields of our closest neighbor.

That is why the CIW is calling for a boycott of Wendy’s across the country, until it agrees to settle for a 1-cent-a-pound increase in wages. No one should be eating burgers in a place that profits from the subjugation and abuse of hundreds or thousands of workers across Mexico or the U.S. That’s why the Immokalee farm workers are calling for the boycott and urging patrons and customers to ask about the source of their food.