Liquid sugar is bad for teeth, but nowhere near as bad as something like potato chips. Food remnants that are high in carbs that get stuck in your teeth and then break down into simple sugars cause way more problems.
If you want to go to root cause how about teaching kids that simple carbs and sugar are exactly the same as far as the body is concerned. Let alone the fact that most simple carbs come with added sugar on top of that.
Personally I didn't really understand that properly until either my late twenties or early thirties.
