you are right, but the problem is that the food that you find in normal supermarkets is depleted of the vitamins and minerals:
Intensive crops have depleted the different minerals of soils; these substances are not reintroduced by fertilisers, which don´t return more than Potassium, Nitrogen and Phosphorus. In addition, pesticides kill soil microorganisms that play a very important role in the "digestion" of mineral matter so that it can be absorbed by plants: this is why the fruits and vegetables that you find in your supermarket also lack minerals.