What a waste. We expect a small size drink to use a small size recipe and smaller amounts of the ingredients. Instead, the small size drink uses the same amounts of ingredients and charges less. Therefore, the costing of the drinks is based on the cost of ingredients for the largest size drink and the small size is overpriced, or the cost of the largest drink is based on the cost of the ingredients for the small size and the rest is just hype. My personal thoughts are that all the drinks are over priced. Considering the size of the drinks is irrelevant in labor and hard costs, then since the cost of the ingredients never varies between sizes, the charges seem to be arbitrary. Now, if I had asked for two identical small size drinks, would I get a discount? I doubt it.
Something should prevent this type of marketing. It is unethical and also very wasteful.