well the lie has recently morphed into the laws slowing and prohibiting soda sales in schools and such all the while promoting juice which can be worse in many cases because people assume its healthy and you cannot over drink because of that
Even the best juice possible (made fresh, raw, organic, and green-leafy vegetables) will be comparatively high in sugar. A 16oz juice requires somewhere in the amount of 4-6 lbs of vegetables and naturally no one would ever consume 4-6 lbs worth of vegetable sugars in one sitting much less 6x a day. With the store bought juices there are also likely fruits added which have even more sugar than green leafy veggies and they store bought juices likely aren't raw (i.e. pasteurized) killing many of the beneficial enzymes and nutrients.