Give a little, sell a lot: How free samples influence shoppers' buying behavior

The supermarket sample is a familiar ploy, but those tasty bites appear to have more impact than marketers imagined. New research from W. P. Carey marketing Professor Stephen Nowlis shows that customers who sample something pleasant subsequently desire more — more of anything good — than those who did not have the treat. Conversely, customers who are exposed to something unappealing end up wanting less. The study has broad implications for retailers.

The supermarket food sample is one of the oldest and most commonly employed tactics of the grocery business. Give shoppers a taste of a new brand of cookie, manufacturers and retailers know, and it's a safe bet those customers will end up buying at least a box or two before they leave.

It just makes sense: Let somebody try something tasty, and they'll come back for more. Then again, if new research from the W. P. Carey School of Business is correct, those increased same-product sales may be just the tip of the iceberg when it comes to sampling's impact.

In a study that tested consumer reaction to a variety of "sampling" situations, W. P. Carey marketing professor Stephen Nowlis — working in conjunction with Baba Shiv, associate professor of marketing at the Stanford Graduate School of Business, and Stanford PhD candidate Monica Wadhwa — found that when participants were treated to a satisfying sample of food or drink, they were not only more likely to want more tasty foods and drinks afterward, but were also more likely to seek out or want any number of other pleasing things — everything from massages to spa treatments to tropical vacations.

The resulting paper, set to be published by The Journal of Marketing Research, is the first to document just how enormously consumer behavior can be shaped through the use of product samples. The work also hints at vast implications in the marketplace, both for manufacturers and retailers. "Our research suggests that sampling drives people to want more of anything that's rewarding," says Nowlis.

"And that's the managerial implication. These sample tables can help not just manufacturers, but retailers as well. Retailers could benefit because customers who try samples seem to want to have a lot more stuff, as opposed to just more of what they sampled. They want all kinds of things."

Do customers get too full to buy?

According to some estimates, grocery stores, restaurants and other businesses spend more than $1 billion each year on sampling initiatives. But even though sampling has been a stalwart marketing technique for decades, the practice is not without its doubters. Critics of the practice offer up what, on its surface, appears to be a sensible argument: If stores give customers too much free food and drink, they risk filling those shoppers up — and, as a result, robbing them of their appetites.

In the process, retailers could also potentially be robbing themselves of profits. Nowlis says this belief isn't all that rare; even some marketing professionals take this stand. "If you give someone a sample of a Pop-Tart, and if they had never tried it before and they liked it, then of course they may be more likely to go buy it off the shelves," Nowlis says.

"In that case the sample is important because, otherwise, they wouldn't know what the product is. But some people have wondered, as a potential side effect, if the sample could reduce their appetite, could leave them saying, 'OK, I've had my Pop-Tart, and now I don't want anything else.'" Remarkably, however, no study had ever been done to test sampling's real impact. Nowlis and his team decided to finally do so.

In the first of a series of studies designed to gauge sampling's impact, Nowlis split 85 test subjects into two groups, both of which were told they would be participating in market surveys. But members of the two groups would have a slightly different experience — a difference based on sampling. The first group was taken to a room where they were offered a small sample of what they were told was a new "sports drink" (in actuality, it was just Hawaiian Punch) being tested for market.

After trying the drink, the participants were then ushered into another room, where they were instructed to watch a documentary as part of a second market study. While watching the show, the subjects were told they were allowed to enjoy free food and drink in the room. The other group of participants, meanwhile, did not participate in the "sports drink" portion of the study — instead, they were ushered directly to the second room, where they also watched the documentary and were offered the same food and drink.

The researchers then measured how much of the free food and drink was consumed by members of each group. The team found that participants who sampled the Hawaiian Punch before entering the second room both drank more free drinks, and enjoyed more free food, than the group who did not test the Hawaiian Punch.

Reverse alliesthesia

The experiment offered up the first, but not the last, evidence supporting the power of sampling — and the existence of a psychological phenomenon known as "reverse alliesthesia." "Alliesthesia" is the notion that one will enjoy food more when one is hungry, and drink more when one is thirsty. It has long been established in the psychological literature.

But according to some more recent work, the phenomenon may also work in the opposite direction — hence the term "reverse alliesthesia." As Nowlis and his team explain in the paper, "reverse-alliesthesia suggests that encountering a consumption cue high in incentive-value is actually likely to intensify rather than satiate a motivational state, thereby increasing subsequent consumption-related behaviors."

Or, put more simply: Give somebody some fine filet mignon, and they're going to want more — even if that first steak pretty much filled them up. "There is a theoretical basis for it," Nowlis says. "There is some literature that suggests you can induce a motivating state by giving somebody a small sample of something, which will then get them to want something more. The literature is making this kind of prediction, but it seems counterintuitive. Because some [marketing people] think, 'Well, if you give people some food or beverage samples, it will decrease their appetite."

Working off the results of their first experiment, Nowlis and the team created a series of follow-up tests to find out just how expansive the impact of reverse-alliesthesia could be. In one of these follow-ups, participants were again asked to sample the same "sports drink" used in the first experiment, and again were taken into a second room.

There, instead of watching a documentary, they were simply asked to rate how much they desired a selection of different items — everything from a juicy steak to a piece of cake, a day at the spa to a vacation in Bora Bora. Once again proving the power of reverse-alliesthesia, the team found that the participants who sampled the Hawaiian Punch before entering the second room wanted the other rewarding items more than the participants who did not get the punch sample.

"Honestly, you don't know what's going to happen," Nowlis said of the study. "But we were a little bit surprised that the results were so general — that if you sampled Hawaiian Punch, you not only would want more punch, but that you would also be more interested in going on vacation. That's the part we were surprised about. It seems like a very robust finding."

Unpleasant experiences count too

But there was yet one more surprise to come: In the final experiment of the study, Nowlis and the team swapped out the Hawaiian Punch and instead tested participants' reaction to sample "smells." Under the guise of a market study for a new fabric guard, some participants in this final study were asked to sniff a pleasing odor (Febreze), while others were given ammonia, and others water.

And, as was hinted by the results of the other studies, those participants who sniffed the pleasing odor went on to drink more free drinks in the follow-up room than those who tested ammonia or water. Additionally, the team found that those who sniffed the ammonia ended up drinking less Pepsi than those in the Febreze or water groups — indicating that, just as sampling a rewarding product can increase appetite, sampling a non-pleasing product can hamper it.

"We found that this seemed to happen on the most general level, and not just for sampling food, but for smells as well," Nowlis said. "Turns out that if somebody even smells something nice, that can stimulate them to want all kinds of things."

Bottom line

• Sampling is one of the most commonly used marketing techniques in the food business, with some estimates stating that businesses spend $1 billion each year on sampling programs.
• Some critics wondered if retailers might be discouraging customers from buying food and drink by giving them free food and drink through samples.
• According to a new study from W. P. Carey, however, these sampling programs are likely highly effective: A research team found that when consumers are given food samples, they tend to seek out more food afterward. The phenomenon is called "reverse alliesthesia."
• In a surprising finding, the team also found that reverse alliesthesia applies even to sample odors — and can lead consumers to want not just food or drink, but any number of rewarding items.