I was just wondering whether anybody knows of a philosopher(s) who have frequently commented and have philosophical ideas on materialism/consumerism.
In the context of the XVII century consumer revolution in England economists and philosophers such as Bernard Mandeville with the "Fable of the Bees" and later Adam Smith with "The Wealth of Nations" praised the social benefits of consumerism. They applauded consumerism as one of the most powerful economic drivers. Even the consumption of the banalest, most trivial and unnecessary goods had the potential of encouraging trade, creating wealth and empowering welfare.
On the other hand, Jean-Jacques Rousseau feared the tremendous consequences of consumerism to the human soul. He called for a return to a much simpler life away from the extreme vanity that characterized the consumer revolution.
As contemporary thinkers, I would highlight Peter Singer for his work on the moral obligation of a responsible and moderate consumption of goods and Slavoj Zizek, who pinpoints the problem of current forms of disguised consumerism and the devastating effects of their waste.