To the average diner, it can often seem like restaurateurs have only recently gotten savvy at using tools like social media to get customers in the door. In truth, restaurants have always used psychology to influence diners. To understand how, look no further than the menu. Chain restaurants and delis often have menus that are physically large, laminated, and easy to read. At more high-end venues, menus tend to be single-paged, with no descriptions or ingredients listed.