Practically unheard of a generation ago, the discounts have become a routine part of many businesses—as common as color televisions in motel rooms and free coffee on airliners.

上一代人几乎闻所未闻的打折已经成为许多企业的惯用手段——就像汽车旅馆房间里的彩电和航班上的免费咖啡一样普遍。