We conduct an empirical case study of the U.S. beer industry to analyze the disruptive effects of locally-manufactured, craft brands on market structure, an increasingly common phenomenon in CPG industries typically attributed to the emerging generation of adult Millennial consumers. We document a generational share gap: Millennials buy more craft beer than earlier generations. We test between two competing mechanisms: (i) persistent generational differences in tastes and (ii) differences in past experiences, or, consumption capital. Our test exploits a novel database tracking the geographic differences in the diffusion of craft breweries across the U.S.. Using a structural model of demand with endogenous consumption capital stock formation, we find that heterogeneous consumption capital accounts for 85% of the generational share gap between Millennials and Baby Boomers, with the remainder explained by intrinsic generational differences in preferences. We predict the beer market structure will continue to fragment over the next decade, over-turning a nearly century-old structure dominated by a small number of national brands. The attribution of the share gap to consumption capital shaped through availability on the supply side of the market highlights how barriers to entry, such as regulation and high traditional marketing costs, sustained a concentrated market structure.