"can someone explain to me why and especially in bread rolls, why they insist on putting sugar in the bread so that it in fact tastes sweet??"
Bread won't rise properly without sugar, but you shouldn't need any more than about a teaspoon per loaf. You shouldn't be able to taste it unless it is brioche or something similar. Croissants always seem sweet too, so they too probably have more sugar than your average bread.
