Loads of people are completely deluded about the levels of exercise - and intensity of exercise - it will take to burn off food. My MiL for example, who thinks that because she goes to tap dancing once a week she has an active lifestyle and can eat cake every day. She refuses to do any exercise at all that makes her remotely out of breath or break a sweat - which is basically the level at which exercise begins to be effective for weightloss. The numerical facts that her weight is creeping up and her cholesterol is too high is completely mystifying to her because she occasionally does Zumba.
This label system seems pretty absurd though - it's far too simplistic to say, oh, 500 cal will take 2 hours of brisk walking to burn off' with no allowance made for body type, sex, weight, age, metabolism, glycemic index of the food, overall diet makeup....