Texture and processing.
First, sugar provides substantial texture, think a lollipop, it’s 100% sugar, take the sugar out it’s a few drops of food coloring and liquid flavoring. If you added artificial sweetener, it would still be a few drops of liquid, it wouldn’t be something you could put on a stick. If you made a sugar free lollipop it needs to be made out of something, and it’s a whole science to get the right texture.
It applies to a whole lot of things, frosting, syrup, etc. Often we use sugar alcohols, but those still have calories and tend to cause a laxative effect.
Second, soda is a very processed food, flavoring and refined sugar mixed with water. Meat and flour are not nearly as refined, and you are not really going to refine the sugar out of those things, I guess you could, but you’re not going to have chunks of pepper in your food, you’re not going to see sesame seeds on your buns. Removing sugar from bread might not be too bad, but from a cheeseburger or a pie is totally different.
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