That terrible! But it seems to be a common misunderstanding. I think it is because we know that the body needs glucose. If your blood sugar drops low, that's bad. So people might think that this means we need to have some sugar in our diet. I used think that when I was a child. It wasn't until I got well into adulthood that I properly understood that we don't need to eat sugar.

The worst thing is if you see somebody sat at a desk in an office drinking Lucozade. It's meant for atheletes who are running fast! But even then, they probably don't need it if they eat properly.