As someone who grew up avoiding sugar and having to look at the back of everything this would have been relatively low in sugar compared to other products sold in that same store in my area. In the South of the US you would have a hard time finding something lower than sprite and or tea(~35g)without alternative synthetic sweeteners like aspertain and sucralose or just water and those options used to be sparce. A lot of times a convenience store would only have diet coke, unsweet tea, or water unless I was okay with 30+ grams of sugar. I'm not saying that it's okay to have that much sugar, but it definitely seems far out of the way from some of the much lower hanging fruit. For example even Gatorade and Powerade have more sugar per package unit and those were available via vending machines IN the school. Also, pretty much every fast-food drink station makes you choose between water, unsweetened tea, or something with almost 50g of sugar when in a can.