Free samples are such a huge part of the Costco Wholesale Corp. shopping experience that there are unofficial rules to govern the occasionally unruly masses.
Don't park your cart in the middle of the aisle while you're waiting for more food to be made, says one writer. Don't think that you can bypass the line by picking over the back of the samples attendant, says another.
Just how out of hand free samples can get was shown this week when a 78-year-old shopper said he was punched in the face after confronting a 24-year-old man about taking too many Nutella samples at a Burbank Costco.
Read more: Costco shopper punched in fight over samples: 'He hit me, and the blood started'
Consumer psychologists say the altercation is just the latest example of consumer behavior that is most notorious during Black Friday shopping: the desire to come out ahead.
"On Black Friday, people will fight tooth and nail to get that last television, but really, if you drill down a little deeper, they're not interested in the product," said Kit Yarrow, author of "Decoding the New Consumer Mind: How and Why We Shop and Buy." "They're interested in winning."
According to a website called Black Friday Death Count, there have been seven deaths and 98 injuries on Black Friday since 2006. In 2010, a woman pepper-sprayed fellow shoppers at a Porter Ranch Wal-Mart, resulting in 20 injuries. In 2008, an employee died after being trampled by a crowd of shoppers at a Long Island Wal-Mart.
The sense of competition around free food samples goes back to social rules, Yarrow said. When a crowd starts to form around a sample table and it seems like someone is taking more than their fair share, it tests shoppers' ideas about community.
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"It's not the 1-inch square of bread," Yarrow said. "It's how can you violate these community rules of fairness? And those feelings started long before the person walked into Costco. They're just acted out in that Costco shopping experience."
The scene at Costco can be particularly intimidating for the uninitiated. The free samples are more plentiful on weekends, when hungry shoppers gather in scrums around tables bearing tiny cups with bite-sized portions. Most recently, customers could try cubes of cheese, frozen burritos and deli meat.
The samples have garnered a large fan base.
Free samples are a particularly effective technique to get shoppers to try something new, especially a food product they might not usually buy, Yarrow said. Plus, there's the added bonus that retailers that offer free samples, such as Trader Joe's or Sam's Club, seem more generous or consumer-centric, Yarrow said.
Costco declined to comment on the Burbank store incident or its free sample policy.
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