Effects of the Door-in-the-Face technique on restaurant customers’ behavior

We tested the Door-in-the-Face technique in a restaurant. After the refusal of a dessert at the end of the meal, waitresses proposed a tea/or a coffee to the customers. This later proposition was addressed immediately after the refusal of the dessert or 3 min later. It was found that the number of customers who ordered coffee/tea was significantly higher in the no-delay condition. Contrast theory was used to explain this effect.