We rarely drink juice. I'm not anti juice, we're just so out of the habit of drinking it, I forget to buy it and when I do, we forget to drink it and it goes bad (or juice boxes sit in my pantry untouched for months). I will buy 100% grape or berry juice to make popsicles in hot weather sometimes and it always ends up going bad in the back of the fridge.
My kids (6 and 2.5) drink water and a couple glasses of milk a day, they occasionally ask for "bubble water", which is just the sparkling water dh and I drink (not soda). They get plenty of fruit sugar, they each have at least 3-4 servings of fresh fruit every day.
I don't think it's necessary and personally believe many kids drink way too much juice. I would rather save the money on juice and eat whole fruits instead.