No, it is absolutely not normal, nor should it be common. As a parent to a 3yo, and knowing other parents with a range of children of different ages, no one is talking about calories or carbs! Myself and others are talking about food and water as fuel, so we can grow big and strong. Our kids know our tummies are happiest with vegetables and meat or chicken etc, but that other foods can be fun and it’s all about balance, moving our bodies is good for happy minds and happy hearts.. etc etc.
sorry to hear that’s the experience of your extended family