Isn't sugar just relatively cheap to produce and can be locally grown in Europe?
One of the "best" sources of "plain" white sucrose (versus fruit's heavier balance of fructose) is sugar cane, which is a plant that prefers sub-tropical regions and often islands at that and historically required massive plantations with slave labor to get cheap and today involve massive expensive industrial harvesters and international cooperation of subsidies, grants, and colonial legacies.
Maple trees grow in northern climates and real Maple syrups are expensive today as a number of subsidies expired and demand outpaced production and even available supply.
Other fruit syrups compete against the primary uses of their fruits.