It’s funny how we often don’t think about what we don’t eat and why we don’t.  Cauliflower leaves are one such example.  Growing up, it’s what protected the food.  Now, it is the food.  When you don’t feel like spending on 101 cruciferous veg - that can cost an arm and a leg in some parts of the world - buy the cauliflower and get the best bang for your buck.