I see it a lot out and about- tiny dots with bottles and beakers full of juice, squash or fizzy drink. I know it's not the worst thing that a young child can be given but I don't understand why it's necessary. I'm an avid squash drinker and happily drink it in front of my charges but they never ask for it. I don't drink tea/coffee so squash keeps me going!
If we were at a party then I don't see a problem with having other things but not on a normal day at home or on a trip out.
It's not even just the teeth element, but the habit it creates (I should know!!) and also the dependency on sugar- there's enough sugar in most foods in a normal diet without the almost saturate of a soft drink.