True, but all of us have very different motivation centers. Some feel that this is the way to lose weight fast. The reasons you mentioned are the results of a Water Fast and will happen regardless of what is the faster's reason to fast, spiritual, religious, weight loss or numerous other things.
I would add that the fast is not a good way to lose weight if after the fast one is going to resort to the same ways of lifestyle which got them to a stage of being obese in the first place.