Food is energy and nutrients. The point of food is to give is energy, I mean why else do we eat?
I do think that some calorie free foods are ok now and again however if they are used very often i think the chemicals can maybe be too much but might also mess with your body. Because food is supposed to give energy, when you eat your body expects energy and nutrients. But then when you eat calorie free foods for example shirataki noodles (which i actually love!) or drink diet sodas, your body doesnt get the energy it expects and messes with your body. You dont get that satisfied feeling either, and the added sweetners in many of the calorie free foods can make you crave more food and often sweet food, which might be the cause of peoples sugar addiction - because they are trying to cut down on calories and eat low kcal food, they actually end up eating more because their body's system is out of whack. I also believe that all the chemicals and additives in those types of foods can cause addiction and make you crave them, such as sodas/diet sodas. It is easy to become addicted to them and then keep drinking them and keep having sweet cravings and making it hard to break a sugar addiction. But like mentioned before.... i think that eating those types of foods now and again is no problem. Do you need to eat them? Of course not, but if someone chooses to, then that is their choice.