Oat Milk Shortage Reveals Which Customers Are Truly Lactose Intolerant

A three-day oat milk shortage at a Brooklyn coffee shop has inadvertently conducted what scientists might call a natural experiment in self-reported dietary restrictions, revealing that approximately 80% of the shop's oat milk customers are, in fact, perfectly capable of digesting dairy. When Grounds for Concern ran out of oat milk last Tuesday, barista Jasmine Roast tracked customer responses to the news. Of the forty-three customers who ordered oat milk over three days, thirty-four accepted whole milk as a substitute without apparent gastric consequences. "I expected distress," Roast reported. "What I got was mild disappointment followed by compliance. Thirty-four people who had been ordering oat milk for months switched to whole milk and were fine. One of them said it was 'actually better.'" The nine remaining customers displayed reactions consistent with genuine dietary restrictions, including visible concern, consultation of phone-based allergy documentation, and in two cases, departure. "Those nine are my real ones," Roast said. "The other thirty-four were oat-curious. I respect the journey but I will never look at them the same way." The shop's owner has declined to comment on the implications for inventory management, noting only that oat milk costs twice as much as dairy and that the shortage saved the shop approximately $180 over three days. The oat milk supply has since been restored, and all thirty-four flexible customers have returned to ordering it, suggesting that the preference, while not medical, is deeply held on an identity level that transcends lactose.