If you look at these 'high end' versions as opposed to say, Lucozade, you're correct in that a little extra has been added. In the most expensive versions 'rare herbs' have been added.
But the base ingredients remain the same. Glucose, Taurine, Caffeine and Sugar. Adding those other additives does little to nothing beyond separating them from the cheaper ones on your supermarket shelves.
It's a case of the Kings New Clothes. Feel free to pay more if you want or if you just like the taste.