A recent article in New York magazine called A Dumb Way Restaurants Trick (‘Trick’) You Into Drinking More Wine implied that it’s true: Restaurants and bars use over-sized wine glasses to trick you into drinking and ordering more wine.
Is it true? Are you being victimized by large wine glasses?
Well, the article actually provides no evidence that using larger than normal wine glasses is a common practice in the restaurant industry. Instead, it described the results of two different studies into wine drinking and portion size. In one, published in BMC Public Health, researchers from the University of Cambridge performed a months-long experiment at a local bar. The bartenders would switch back and forth between a regular-sized wine glass (300 ml) to a slightly smaller one (250 ml), and then to a slightly larger one (370 ml).
After four months, the receipts were added up and it was found that on the over-sized wine glass nights, the bar sold more wine. The reason why customers ordered more wine when drinking out of big glasses is not precisely known but, ostensibly, the reason is simple: The pours in the big glasses looked smaller so people felt like they were drinking less, and so ordered more. On average, this amount turned out to be ten percent more, a significant figure for a restaurant or bar!
The other study the article mentions was by Brian Wansink at Cornell Universities Brand Lab. In this study, when people served themselves white or red wine, they drank nine percent more white wine than red wine. Now, I would guess the reason why is red wine is cloying and who would want to drink a lot of it? But, the supposed reason is that the red wine just showed up against the glass better, making a slightly large pour of white wine less noticeable (I’m going with red wine doesn’t taste as good as white wine, though).
Note: Since writing this article, Wansink’s studies have been widely discredited for various alleged incidents of scientific malfeasance. The biggest reason stated data manipulation and reporting only positive results. It is possible the study mentioned here should be called into question, as well. I myself followed his research until I began to grow a bit suspicious of the sheer volume of ‘positive’ results, and the sheer volume of research in general. I thought salami slicing was the problem but the abuses seem to have been much broader.
Here’s the problem: These are closely controlled experiments. In reality, in settings where, for example, waiters are pouring wine by the glass, a big problem for restaurants is over-pouring.
A standard stemmed wine glass has a bowl of 8 ounces or 9 ounces. However, the standard serving is 5 ounces to 6 ounces. Whether you know it or not, when you order wine by the glass in a typical restaurant, you are usually being under-poured or over-poured. Where under-pouring cheats you, the customer, over-pouring cheats the restaurant owner out of profits.
If a restaurant were to serve wine in over-sized glasses, sure, the guest might drink more, but the waitstaff, or even the bartenders would probably over-pour! As a strategy to fool you into drinking more, the joke is on the restaurant. The profit is in getting as many servings out of the wine bottle as possible.
It is difficult enough for a restaurant to ensure consistent pours, especially given the larger turnover of waitstaff. Not only do staff need to be trained on the proper pour, but they need to be able to pour this amount consistently. In restaurants where “proper” red whine and white wine glass are used, this problem is probably compounded. Red wine glasses typically have large round bowls with wider mouths where white wine glass have more narrow bowls and mouths. Switching between these two sizes would make it that much more difficult to ensure consistent pours.
To fool us into ordering more by using large glasses, the restaurant would have to ensure that the pours were still precisely right, so that they weren’t pouring profit down our gullets. And, switching back and forth between glasses would not be possible as this would just cause more confusing and more mis-pouring. All the glasses would have to be replaced. Although I do not know whether a large number of restaurants are using over-large wine glasses, it certainly is not a sure-fire way to increase profits. It would take a concerted effort on the part of management, and the controls would need to be precise. Since it is hard enough to get pours consistent in the first place and keep them that way, it seems unlikely that many restaurants would want to adapt a non-standard wine glass size, unless they actually planned on over-pouring huge amounts of cheap wine, a completely different strategy employed in some restaurants, usually Italian.
In a restaurant pushing wine by the bottle, however, the large glass gambit could well pay off. When guest pour wine themselves, they are going to tend to pour more than a “standard pour” in any case. If they perceive the amount they are drinking to be less, due to the large glass making the amount of wine seem smaller, then indeed they might drink more and order more bottles of wine.
Where restaurants have well-managed wine programs, it is doubtful you will see giant wine glasses. When they are used, it is difficult to say how many restaurants do this for a scientific reason to use human behavior to increase profits. Just as likely, they do not know any better and figure bigger glasses will make customers think they are getting more, while in fact, ensuring they actually are getting more.
Keep in mind that the wine glasses used in the experiment were only slightly larger or smaller. If a wine glass were to become too large, then any pour would start to appear too small, including, of course, a standard pour. There are styles of red-wine glasses that are 19 ounces or even larger. If you pour a standard portion into these glasses, the glass is only filled to about twenty percent, looking quite small. In order to not appear as if you were cheating a guest, you’d have to over-pour. Restaurants may sometimes use very large wine-bowls to make it easier to swirl the wine, and for the aromas to develop, but there is an obvious trade-off, so that the size of the glass has to be balanced with the perceived size of a pour.
This should not be taken as a proper discussion of wine glasses, of course. There are many different sizes and varying shapes of wine glasses, each of them meant for specific types of wine. Most restaurants use one or two standard glasses, however. A restaurant may well decide on a certain glass simply because of the look of the glass. If the glass is a bit larger, making a ‘standard’ 5-ounce pour look too small, the restaurant owner may well feel it is worth it to increase the size of the standard pour to say, 6 ounces.
More Wine More Tip?
Ultimately, as already suggested, the size of the wine pours rest in the hands of the bartenders and/or the waitstaff. There is one reason why a bartender doesn’t want to cheat guests with stingy pours. More wine can equal bigger tips. A bartender may not necessarily cheat his owner by over-pouring, but cheating his customers by under-pouring would be just as inadvisable.
The bottom line is that there is no evidence that a conspiracy of over-large wine glasses designed to trick you into ordering more wine is at hand. The evidence from the studies suggests that you can be fooled, not that you are being fooled. People who drink wine are quite likely to expect a glass to be filled to a certain extent. A bigger glass with a ‘small’ looking pour, while it may trick the mind into thinking you’re drinking less wine, may also trick you into thinking you’re being cheated with stingy pours. The only way to know what is going on at the restaurants or bars you frequent would be to bring a measuring cup and measure the wine you are poured! For the most part, by the glass pours have gotten larger, not smaller.
If you order by the bottle, however, be aware of the effect of the glass on your perception of the wine volume.