Conspicuous Consumption? Yes, but It’s Not Crazy:

One common claim is that the wealthy routinely violate the economist’s law of demand. A bedrock principle of economic rationality, this law holds that as the price of a good rises, consumers buy less of it. Many analysts, however, portray the rich as people who lust after what are known as “Veblen goods” — commodities whose sales actually increase when their prices rise