Final answer:
Thorstein Veblen criticized the late nineteenth-century capitalist society in his book The Theory of the Leisure Class. He targeted the practice of "conspicuous consumption" and its impact on the working class.
Step-by-step explanation:
Thorstein Veblen criticized the late nineteenth-century capitalist society in his book The Theory of the Leisure Class. He targeted the practice of "conspicuous consumption", which referred to the middle class's focus on personal comfort and consumption rather than production. Veblen argued that this exploitation of the working class by nonproducers and the creation of business trusts only widened the wealth gap and caused economic inefficiencies.