I have always took issue when serving sizes are less then the full package or can. Let's get real here, who opens up a can of soup and doesn't eat the whole thing? Does anyone actually dole out 2.5 servings?
Well, according to the NYTs very few do:
A similar number of the people asked, 61 percent, said they would also eat the entire can of a condensed soup, like Campbell’s Chicken Noodle, which lists 2.5 servings per can. A single serving contains 890 milligrams of sodium, and the full can has 2,390 milligrams. About 27 percent of respondents said they would eat just half a can in one sitting.Also enlightening is the "zero" calorie claims of cooking sprays:
Another product that made the list of egregious offenders was cooking sprays, which list nutritional information based on “ridiculously tiny serving sizes,” the group said. One of the most popular, PAM, boasts zero calories and zero fat on the label of its original canola cooking spray. But that information refers to a spray lasting just a quarter of a second.
“That’s just not the way people use them,” Mr. Jacobson said. “It’s probably impossible to spray for a third of a second. We suggested six seconds might be kind of reasonable.” A six-second spray, he said, has 50 calories and six grams of fat.