That's a good point. I would say it is a combination: the amount of food you eat at once vs. the amount of energy you spent (sports/working). You can eat a lot

That's a good point. I would say it is a combination: the amount of food you eat at once vs. the amount of energy you spent (sports/working). You can eat a lot of carbs over time when being physically active. But once you stop being as physically active, you have to adjust your carbs accordingly. So what OP says is correct for how most people live nowadays.