That sudden midday craving for fries and a shake? It’s no accident, and neither is the “impulse” splurge on a soft drink or dessert. Subliminal messages are mostly the stuff of science fiction, but fast-food restaurants have all kinds of subtle tricks to lure potential customers in and keep them spending once they’ve walked through the doors.

Read on to learn how McDonald’s, Chipotle, Taco Bell, and others at the top of the industry keep their business booming.

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