The “Fight for Fifteen” campaign to raise the wages of workers in fast food and other low-wage industries has prompted much speculation about the automation of restaurant work. But the mechanized delivery of meals isn’t just the possible future of fast food—it’s also the way the industry got its start.

In a 2000 paper for New York History, Nicholas Bromell recounts the way automats created a bridge between early-twentieth century cafeterias and the opening of the first McDonalds and Burger King restaurants in the 1950s.

Bromell wrote that cafeterias were, themselves, the fast food joints of turn-of-the-century America, criticized for the “hasty, gulping style of eating” they promoted. Their food was cheaper and healthier than offerings from street vendors and diners, and they let urban workers grab a quick lunch and get right back to the job.

The first automat in New York City opened in 1912. Diners chose a selection from a “wall of tiny glass windows displaying a high-rise of culinary delights,” Bromell writes. They dropped some nickels in a slot, turned a knob, and took their food. The kitchen ran just like any other cafeteria operation, replacing the food as it was sold, but the automated vending kept lines from getting too long and reduced the opportunities for unhygienic food handling.

Automat owners emphasized the “scientific” dining experience with art-deco furnishings. The clean, streamlined feel helped convince the public that they were appropriate places for women as well as men.

Prefiguring McDonalds, automat chain owner Horn & Hardart standardized their food in new ways. The corporation set recipes and preparation methods down to the size of the bacon square to be placed on top of a serving of baked beans.

Still, aspects of the experience would be strange to a modern fast-food customer. There was no take-out, let alone a drive-through window. People sat family-style, side by side with strangers at a table, and they ate on hand-painted crockery with real flatware.

Bromell writes that automats thrived in New York City more than anywhere else in the country, thanks to the crowded city streets streaming with commuters walking from subway stops to office buildings. After World War II, many corporate headquarters moved out of Manhattan, and many New Yorkers adopted a suburban, car-based lifestyle. Meanwhile, the thrifty Depression mindset that made bare-bones eateries popular transformed into a sense of prosperity in the post-war economic boom.

Horn & Hardart tried to follow its customers into the suburbs, opening conventional restaurants and opening a division to sell its food through mail order and supermarket channels. Eventually, the company found a solution that stuck: Burger King. The company opened the first New York City location of the fast-food franchise and expanded from there, eventually adding franchises of other brands like Arby’s and The King’s Table as well.

The corporation didn’t need to change its model all that much to run fast food places. The keys were still consistency, cleanliness, quick customer turnover, and low price.