Well, yes, consumerism is a problem, but in my experience it is equally spread among (almost) the entire income spectrum. The only major difference I see is about what kinds of goods and services do people blindly consume depending largely on their income. Two exceptions I see are both the extremely rich and the extremely poor.
In fact that's why in my personal life I first and foremost differentiate consumers and producers and seek out producers. I can't be bothered to endlessly engage in conversations about watching movies, vacations, new gadgets and so on. I want to know what people create, regardless of what it is.
Lately it seems more and more as the most important categorization tool at hand. Not wealth, not beauty, not intelligence, not anything else, just whether a persons most intimate, passionate desire is to produce or to consume.