I think you're mistaking consumerism for capitalism.
Consumerism being the idea that more, more, more, at any expense, is the most effective and efficient way forward. I would certainly agree such a view is prevalent, dangerous and outright stupid.
I would not agree that people's futures and material security, etc, on the whole, depend on consumerism. People can act as capitalists without being consumerists (ie, you can buy seedlings without buying every seedling you can cram into your yard).
I think, in Australia at least, capitalism and consumerism have a complex relationship - in the USA consumerism has essentially replaced capitalism, here I'm not sure, I certainly hope not, but I couldn't rightly say.
Capitalism, of course, provides it's own host of issues and problems, but I strongly disagree that reducing consumerism reduces a person's ability to make a living. Levels of consumerism do not affect me in any way (which is either/both a strength and a weakness).
"Hatred never ceases by hatred; but by love alone is healed." - Buddha.
To live only for some future goal is shallow. It's the sides of the mountain which sustain life, not the top. - Robert Pirsig.