Time is money，but that principle means different things for different types of restaurants.Unlike fast­food places，fine dining shops prefer customers to stay longer and spend.One way to encourage customers to stay and order that extra round：put on some Mozart(莫扎特)．When classical，rather than pop，music was playing，diners spent more.Fast music hurried diners out.Particular scents also have an effect：diners who got the scent of lavender(薰衣草) stayed longer and spent more than those who smelled lemon，or no scent.