A new study from the NPD Group , conducted in partnership with Stylitics , examines how people shop for one of the most popular (and profitable) fashion categories: handbags. It's a pretty lucrative business, according to the report. Last year, women 18 and older in the U.S. spent $11.5 billion on handbags — up 5% from 2014. But most of that growth came from baby boomers: Millennial spending in this category only went up 2%, according to the study. Why? The way that the oft-discussed 18-to-34 age group goes about snagging a new bag has changed markedly over the years.For millennials, it's less about logos and more about the actual product — the details, the structure, and the function they can get out of a handbag. (Hey, you can't have just any old Insta-bag .) Additionally, impulse buys aren't as much of a big thing. Of millennials polled for the study, 41% said they spent at least a month (or more) thinking about which bag to buy. This consumer is more likely to really do her research, often seeking out emerging labels in lieu of purchasing solely because of a status-y designer name."This [millennial] customer starts with specific product attributes, not brand, when looking for her next handbag, and invests more time and research in her purchase than brands and retailers realize," Rohan Deuskar, CEO and cofounder of Stylitics, said . "These findings have been eye-opening for handbag sellers, and are having an immediate impact on their marketing, merchandising, and product development strategies."Marshal Cohen, chief industry analyst at the NPD Group, characterizes this bag buying process as a "journey," where multiple factors and considerations come into play. "The handbag has become a signature item, and retailers need to take advantage of selling it in-store, up-front and center, as their own signature," Cohen said in the report.The decline of flashy logos has been looming over the luxury space for a while now, so this may just be another reason for labels to refocus their branding. Either way, these habits certainly make for good bag stalking