Oooooooh I love this argument...just spent 60 mins going through the same thing with the organisers of the forthcoming Loch Lomond Food and Drink Festival - (8th & 9th September at Balloch in case you wondered).
The factory processed foodstuffs need to give information about the contents of the products included and there has been some rationalisation of terms used of ingredients. In this instance, the term 'sugar' is insufficient information to be used, and the 'gluco etc etc etc' term is too 'chemical'. But is it a sucrose octaacetate, or sucrose benzoate, or a sucrose stearate, etc etc??
As there are numbers of consumers who have allergies or conditions that preclude eating or even touching certain ingredients etc, they are given details using standardised terminology to look for in ingredients labelling.
In the case of sugar, there are loads of types and problems associated with them - lactose intolerance is one a lot of people have heard of and that is present in milk and milk by-products. And glycosuria - a problem where sugar is passed in urine - is one of the ailments that sufferers need to have information about amounts or presence of sugar. Diabetics also use varying terms for sugars too of course.
In general, a rationalised name for ingredients on labelling allows for standardised naming of products. Allergies are getting so common - sunflower oil has become one of the rising problems - and as many of the chemically enhanced ingredients actually come form such things as 'distillations' of petrol - true! - it is esential we give up processed muck and just eat proper, simple, seasonal food I reckon....