the only reason people still eat it could be because no one really cares about what's in it, we just care about its taste, its smell, its appearance, and its reputation. (plus people are materialistic, they'll hide anything to get they money)
Eating junk food on a regular basis can lead to an increased risk of obesity and chronic diseases like cardiovascular disease, type 2 diabetes, non-alcoholic fatty liver disease and some cancers. We know Australian's eat too much junk food. 35% of adults' daily energy intake (kilojoules) comes from junk food.