I don't find that weird - if I'm going to be drinking a coke (of whatever flavor), caffeine-free Diet Coke is my preference over regular/Zero. It is a different formula, even if it only comes down to the blend of sweeteners. Obviously I don't know the actual formulas, but each has a different blend of sweeteners based on the labels, and now I've added "The Real Thing" to my reading list. Different people prefer different blends, like the other commenters who prefer monkfruit, erythritol or stevia.