Black Friday is ballooning—the ritualistic shopping frenzy on the day after Thanksgiving is now just one part of a $50-billion weekend of commercial excess that includes Small Business Saturday and Cyber Monday. Generational shifts are even driving an increase in businesses open on Thanksgiving Day. According to a survey by the National Retail Federation, about 26 percent of 18- to 24-year-olds plan to shop on the holiday itself.

"Millennials are accustomed to being able to buy whatever they want to buy, and buy it right now," says Jane Boyd Thomas of Winthrop University, who studies the psychology of shoppers. But the tech-savvy generation is also less concerned with finding deals on a particular day, because they already do so much of their utilitarian shopping online. "We no longer have to wait for Black Friday to find a deal," Thomas says. "We can find them all the time. We can price match all the time. We've become accustomed to deals because we're bombarded with them."

Still, on this year's Black Friday, the National Retail Federation estimates that more than 95 million Americans will rise with the sun and race through crowded stores competing for bargains. Why do they do it? Together with her colleague Cara Peters, Thomas found that Black Friday delivers an experience that other types of shopping don't quite match. The pseudo-holiday blends family bonding and competitive adventure to create an intoxicating package. In a 2011 study of Black Friday veterans, Thomas and Peters found that the excitement and accomplishments of the experience cause groups of family members or close friends to take on a military mindset.

“The typical Black Friday shopper is a person who is on a mission,” says Thomas. “It's part of their family's tradition, and they've been doing it for years.” Based on their interviews, the experience can be broken down into four main themes:

Intense Bonding

Black Friday fans think of the day as an extension of Thanksgiving, in terms of spending quality time with family and friends and bonding through the sometimes intense experiences. Members of these tight-knit groups also enjoy the sense of sharing a communal ritual with other shoppers on similar quests.

“Just like when you go to a movie theater or amusement park, you're sharing that experience with strangers,” says Thomas. “It may be chaotic, but you're sharing it. Some bad things may happen, but good things also happen, and you see those random acts of kindness that always occur. So it's really a cultural phenomenon for that person who is going to shop on Black Friday.”

Strategic Planning

The different shoppers from the study were nearly united in their focus—everyone is on a mission backed by a detailed strategy.

“They sit down and map it all out,” says Thomas. “'I'm going to Walmart, and when I'm there I'll get a Barbie and a G.I. Joe, the wrapping paper and a flat screen TV.' The day is mapped out to the point where groups identify who is going to drive and who should stand in which lines.” The research also shows that focused Black Friday shoppers know what deals they want, and they often target only those items, ignoring other in-store promotions.

The Great Race

Many of the study participants alluded to thriving on the day's competitive nature, describing it as a “race” or “mad dash” to grab prized purchases before others can get them first.

“Its fun to try to get as many bargains as I possibly can in a limited amount of time. It’s like a game show,” one interviewee told the authors. “It’s competitive in the sense that everybody is trying to be near the head of the line and get the sale item before everyone else.” This competition creates an exciting adventure, the authors noted, complete with the enjoyable swapping of “war stories” when the day is done.

Mission Accomplished

The study's shoppers shared the same definition of success: Finding the most coveted items in stores, because they are often hidden away or surrounded by a gauntlet of other merchandise, and buying them at big savings. “At the end of the day they get to come back and lay out all the purchases, tally up savings, and say 'we accomplished our mission, we did great today,'” says Thomas. “And there are some bragging rights involved with that.”

Thomas thinks that within five years or so, changing habits and preferences will make the actual date less of a retail juggernaut. But the psychological reasons why people participate in Black Friday probably won't change much, and the practice won't fade away anytime soon. “There are still those people who have a family unit or group of girlfriends and enjoy this as part of their tradition,” she says. “And it's going to stay part of their traditions.”