It's because fructose is a carbohydrate. At present I am limiting carbohydrates, all of them, and the only fruit I'm eating is one orange daily. I'm also limiting milk because of the lactose content.
Honey is also a carbohydrate but it is what our ancestors used for sweetening before cane sugar was discovered. They didn't have 'sweets' in the sense that we mean now - chocolate etc - so they wouldn't have had so much of it.
Anything ending in 'ose' is a carbohydrate, but fructose is naturally-occurring and therefore we eat much less of it than we do of sucrose, which is added to almost all the processed foods, ready-meals, fast foods, you name it. It also comes combined with vitamins whereas sucrose comes combined with nothing.