It’s not necessarily a matter of self-control, as the industry’s goal is to override your appetite. In the process of doing so, they put unreasonably huge amounts of sugar in everything packed. Some sodas give you 70 grams of sugar per can/bottle.
Have you ever had regular coffee or tea that you sweetened yourself? I get full to use three or four cans/cubes in my coffee sometimes and feel self-conscious about it. And the thing is, these three cans actually contain 5 to 9 times less sugar than common soda and coffee shop drinks.
Companies that sell flavorings, beverages, and packaged foods are in an arms race with each other to make their products as irresistible as possible, and in an effort to attract us as customers, the entire industry has essentially engineered foods to keep us hungry.
Sugar as a macronutrient is not a vile all over, because if you leave it to your own devices with unprocessed foods, it is very likely that you will eat much less sugar even if the sugar is freely available to you to put in your foods in any amount you want.
I’m on mobile now and I’m too lazy to coordinate links but check out the work of Dr. Hall and Dancinger at the National Institutes of Health. They and their team are very reputable and have gone into great detail about processed foods and how they leave us unsatisfied despite their high energy content.