Sugar is not addictive nor is it "much more harmful than alcohol". No one out there is just eating spoons of sugar because of its addictive properties.

Your post about obesity doesn't imply it's all about sugar.

One of the reasons obesity is such an issue is because of the combination of sweet and savoury foods that are very calories dense and not very satiating.

Basically every culture is built around the consumption of carbohydrates, which are all similarly easy to absorb like sugar. Rice, Potatoes, Bread, it's all in the same category in my understanding. An easy source of burnable energy, easier to break down into the "right kind" of carbon rings than e.g. fat. The comparison is kinda weak, this is literally one of the pathways of our basic metabolism. Unlike alcohol, which has a complex and toxic pathway to get anywhere.

Please provide any scientific evidence of your claim.

Heroin is fine in moderation! /s

The thing is that it's impossible to moderate one's intake as, as you said, it's addictive.