At the Cafe Gratitude restaurant chain in California, waiters serve plates of vegan rice bowls, vegetable pizzas and tempeh sandwiches with names such as “Gracious,” ‘’Warm-Hearted” and “Magical.”

The last two weeks, though, have been anything but kind.

Angry patrons and animal rights activists are calling on vegans to boycott the restaurants after learning that owners Matthew and Terces Engelhart have begun eating meat and consuming animals raised on their private farm.

“The brand has betrayed my trust by turning around and killing the animals that trust them on their property,” said Anita Carswell, a communications manager for In Defense of Animals who says she won’t eat at Cafe Gratitude again.

Though the restaurants continue to serve only plant-based food, the couple’s decision has provoked a heated backlash in a state where vegan restaurants and juice bars can be as easy to find as burgers and barbecue.

Death threats were left at the couple’s Be Love Farm in Northern California and demonstrators gathered outside a Cafe Gratitude restaurant in Los Angeles last week. Meanwhile, groups such as In Defense of Animals are calling on the couple to turn their farm into an animal sanctuary.

The Engelharts themselves declined an interview request, but Terces Engelhart’s son and Cafe Gratitude’s chief operating officer said the feud against Cafe Gratitude has unfairly cast his mother and stepfather as deceptive animal killers.

“I personally feel it’s a little illogical to require my parents to remain vegan for the rest of their lives just because they created a vegan restaurant at a point in time that they were vegan,” Cary Mosier said.

The family’s chain includes six Cafe Gratitude restaurants and two Mexican vegan eateries called Gracias Madre in Los Angeles and San Francisco.

Matthew and Terces Engelhart were vegetarians for nearly 40 years, but decided to return to eating meat after leaving San Francisco and starting a farm about 55 miles away in Vacaville. They started with eggs and cheese from the farm’s chickens and cows. Then, after one old cow had to be put down, they decided it made sense to incorporate meat into their diets as well.

In a blog post, Terces Engelhart wrote the transition was a “necessary and important part of our own growth as well as the sustainability of our farm.”

The entry was posted in February 2015 but went largely unnoticed until a few weeks ago, when it was shared and went viral on vegan and animal rights websites. The couple is now being inundated with messages on Facebook and social media forums criticizing them as “flesh eaters” and calling them hypocrites for owning vegan restaurants but eating meat at home.

“If they market themselves on ethics, they should follow through on that,” Carswell said.

Mosier said his parents have “literally two cows,” and his mother dotes on them, even rubbing them regularly with coconut oil. While the restaurants are vegan, he said the company has never promoted a “meat is murder” viewpoint.

“I understand people can disagree with eating meat or killing animals,” he said. “But to put those beliefs on another person and call them a liar if they don’t do it, I think, is heading in the wrong direction.

“And if you’re a vegan, why would you want to close and boycott, frankly, the largest vegan restaurant group in California?”