Robin Hanson posits, based on the peculiar ineffectiveness of advertising, that in fact brands signal identity. It's been observed that we're seeing wealthy countries move from an identity model where identity is determined by what we produce to one where we choose how to signal it based on what we consume. Concretely: relative to 30 years ago, today you're less likely to hear someone characterize herself as an accountant (or she will do so to less of a degree) than as a wine connoisseuse, Lady Gaga fan, etc.
There is a general argument, most famously made by Tyler Cowen, that economic growth in wealthy countries will remain indefinitely sluggish relative to previous decades because there is a great stagnation, possibly because we're now wealthy enough to turn non-productively inward. A consumption-based identity accords well with that idea.