People are bringing their own food to Bay Area restaurants. Is ‘purse tuna' ever OK?

Diners are increasingly bringing their own food, including entire pizzas, to restaurants. (Steven Boyle/S.F. Chronicle)
A few years ago, Akira Akuto was dining at Quarter Sheets, a popular Los Angeles pizzeria. Akuto, a chef, watched as two people from the party of eight next to him left and returned with a box of pizza…. from a different pizzeria. The couple hid it under the table, surreptitiously taking bites of the contraband slices, until a server confronted them.
This is a restaurant, she said. You can't bring food in from another restaurant.
Akuto was shocked, as was I when I first heard the story. But as I've spoken with restaurant workers over the last few weeks, I've learned that this behavior is not as far-fetched as I would have imagined. And so, here's a sentence I never imagined I would need to write: Readers, please do not bring your own food to restaurants.
My journey into the dark underbelly of the BYOFood movement began with a direct message from Contimo, a Napa cafe that serves breakfast and lunch. "We've noticed a surprising and increasing trend: guests bringing outside food - or even homecooked meals - into our restaurant," owner Ryan Harris wrote. "It's now a daily occurrence." He wondered if other businesses were also dealing with this situation and, if so, how they were tackling it.
Surely this was a fluke, I thought, a quirk particular to Napa tourists who have overdone it at the tasting rooms and forgotten that we live in a society. But I decided to post about it on Instagram, asking restaurant workers if they had encountered customers taking a potluck approach to dining out.

Contimo Provisions Ryan Harris speaks with customers. He has noticed an uptick in diners bringing their own food into his Napa restaurant. (Brontë Wittpenn/The Chronicle)
"Mostly drinks," an employee at Tartine Manufactory responded, "but I had to politely tell a guest the other day that we don't allow outside food. They brought in what looked like a rice dish with barbecue pork."
"Sometimes we have people who want to bring in their own pizza toppings," wrote Aimée Wingen of Wingen Bakery in Livermore, "like out-of-season tomatoes or arugula or, one time, even their own chopped gem lettuce."
"Once a lady pulled a whole rotisserie chicken out of her purse and started putting it on her salad," Katie Reicher, the chef at the famously meat-free restaurant Greens, told me. On another occasion, there was "purse tuna," two words that I wish I had never seen side-by-side.
What was inspiring this madness? If you want to keep up with the most awful of trends, there's only one place to go: TikTok. There, I quickly found a subgroup of diners encouraging one another in their quests to smuggle their own food into restaurants.
Many of these content creators are body builders, powerlifters or other fitness enthusiasts who obsessively track their macros. In one video, a 16-year-old prepping for a body building show asks her followers if it's acceptable to bring her own food to the restaurant where her friends will be dining before winter formal. She ends the video by saying, the uncertainty audible in her voice, "I feel so weird having to do that, but it'll be worth it in the end?" The comments applaud her for sticking to her #goals.
Hercules Nutrition and Training, a team of Indiana-based personal trainers and coaches, posts videos about how to boost testosterone alongside recipes for anabolic French toast. Much of their content focuses on "24/7 accountability," encouraging their followers to adhere faithfully to their diets in order to get shredded for summer. "I just went to BJ's the other day with some friends," one of the coaches says in a video, "and I brought my own food. And there's nothing wrong with that."
That sentiment is echoed by TikTok creator @joannamiss2, a mom of three whom I can best describe as an egg salad influencer. Depending on which way you look at them, her videos about bringing egg salad sandwiches to restaurants are either algorithm-savvy rage bait or the incredibly earnest ministry of a woman who shan't be parted from her eggs and mayo. It all starts innocently enough; she has young children, and she likes to pack them a little something in case they won't eat off the menu. Another video features her husband, who is gluten-intolerant, explaining that Joanna has made him an egg salad sandwich to bring to a pasta-centric restaurant.
But at a certain point, Joanna gives up the pretense of needing an excuse - picky kids, dietary restrictions - for bringing egg salad anywhere she pleases. "I'm going out to eat with a bunch of friends tonight," she says to the camera, potato masher hovering menacingly over three hard-boiled eggs, "and I don't know if I'm going to like anything at this restaurant."
To her haters, Joanna says, "You're allowed to bring your food to the restaurant… It's a normal thing in times where everything is just so expensive." While Joanna did not respond to my request for an interview, I did manage to speak with someone who agrees with her, at least to a point.
Margaux Bauerlein is a recent college graduate and one of our summer interns here at the Chronicle. When she heard I was writing about bringing outside food to restaurants, she piped up - she had seen this practice firsthand while working at La Val's Pizza in Berkeley, and, on the flip side, she had engaged in the behavior as well. As a college student, it often was a matter of budget, Bauerlein told me, and the fast-casual restaurants surrounding UC Berkeley could easily feel like an extension of the campus cafeteria. A group of friends might all individually order the takeout of their choice at their preferred price points before meeting back up at a central restaurant to eat together.
Bauerlein clarified that she would be mortified if a friend showed up with her own food at an establishment with table service. "Do I have to make eye contact with my waiter?" she asked. "That's where I draw the line." But if a restaurant is a counter-service operation, she feels it's more permissible - especially if there is outdoor seating.

Customers walk into at Contimo Provisions, a counter-service spot with outdoor seating in Napa. (Brontë Wittpenn/The Chronicle)
Contimo checks both of those boxes, which is perhaps why Harris has seen an uptick in customers with entire pizzas, spring rolls and even homemade salads. "The only way I've been able to make it make sense of it," Harris said, "is that our style of hospitality makes people feel comfortable, and then they get too comfortable. But they forget this is how we make a living."
There is one type of "purse tuna" customer that Harris appreciates: diners with major dietary restrictions. He's is happy to accommodate dietary needs as possible - macro bros, feel free to ask for double meat on your sandwich instead of sneaking in your own meal prep - but in cases where someone wants to swap in their own, say, gluten-free bread? Go right ahead. "I love those guests," he told me. "That's someone who is saying, ‘I have an accommodation you might not be able to meet, but I still want to support your restaurant.'"
Rounak Dumra of Hayward's Wah Jee Wah, which offers mostly outdoor seating, sees this often, and he feels the same way. He'll even allow customers to order a pizza from his neighbor if they're dining with kids who are skeptical of his Indian barbecue. What he doesn't understand is guests who bring their own rice - a staple item that he offers on his menu.
I asked if he had any advice for Harris and other business owners in similar situations. "You know how when people bring in their own wine bottles, they're charged corkage?" he mused. "That would be interesting. Maybe that would discourage people."