A middle-aged husband is finishing eating a dessert when his wife walks in and catches him. She says, suspiciously: “Hey, what are you up to?” And he says: “What are you trying to insinuate?” And she says: “Me insinuate? In sin you ate!” And he says he didn’t sin, because it was (whatever brand of) healthy, low-calorie dessert that he ate. And his wife says if that ’s the case, she would like one too. So her husband gets one for her to enjoy.
And the next ad in the campaign could use “in fat you ate”, where we see someone finishing up eating another of the diet desserts, this time a brownie, and when a friend walks in, they ask our heroic dessert eater what they were eating, and our hero says: “A delicious brownie. I love brownies.” Then their friend says: “No, it’s infatuation, because in fat you ate.” And to this, our heroic brownie eater says: “In fat I did not eat: this is a (whatever brand of) low-fat brownie.” And so the friend says: “Really? It sure looked good. Do you have another?” And so our dessert-eating hero pulls another brownie from his/her bag, and gives it to his/her friend to enjoy.