A necessity is something that people will buy whether the price is high or low. This makes the price in-elastic, because there is no need to change it to fit the demand. Demand and quantity are almost always the same. A luxury is something that people will only buy when they have the money for it. This makes the price elastic, since it needs to raise or lower to fit the demand curve. | A necessity is something that people will buy whether the price is high or low. This makes the price in-elastic, because there is no need to change it to fit the demand. Demand and quantity are almost always the same. A luxury is something that people will only buy when they have the money for it. This makes the price elastic, since it needs to raise or lower to fit the demand curve. |