The economic reasoning for airlines is used to gather consumers between vacationers and business travelers depending on the time of day, age and the date of purchase. The reason airlines do it is because they know the consumer will pay the higher price when needed. Movie theaters economic reasoning is based on age. Children, younger adults and elderly people having a less than normal salary rather than average aged adult, who can probably afford a full-price ticket. Movie theaters do this to keep low-income groups going to movies without giving a discount all of this is based on what the consumer is willing to pay. the requirements for practicing price discrimination comes down to several different things. The market must have a downward-sloping demand curve, so they can increase prices without losing all its customers. Consumers with different demand elasticities must be separable into submarkets. Differences rise from salary differences, the customers likings and locations. Another requirement is the business cost is a smaller amount than the profit, so the venders must separate consumers in order not to create arbitrage.