Good bread for $0.50/loaf? By what metric is it good? It tastes good? I never disputed that cheap bread can taste good. It has a token amount of good additives? Sure, you can do that, and it makes the bread sound healthy, without actually being healthy.

Let's assume the loaf is 1 pound (likely slightly more). You claim $0.50 ingredients in that 1 lb. Cheap flour is what, I see $0.02/oz at walmart (25lb bulk), so that's $0.32 per loaf, max. You've added 18 cents of other ingredients. (Edit: factoring in water, more like $0.15-0.20 of flour, so 30-35 cents for healthy additives). You can't buy much with 35 cents. The bread is still a bunch of empty carbs combined with some healthy food (baked, so a bunch of the nutrients are reduced. You can make more expensive bread that's 1 or 5 dollars too, it doesn't change the fact that bread is mostly empty carbs, plus whatever you added that you could have eaten separately and gotten more nutrients from.

You seem to think the only "good" bits of bread are seeds and nuts some people add. That is not bread. Bread is water, flour and yeast, and salt optionally.

Great bread doesn't have to be expensive and it doesn't need anything extra. And "healthy additives" doesn't make bad bread good.

Like 1/3 or more of the weight of the final product will be water.

There's also really nothing wrong with calories. Most people need something like 2000 a day, leaves plenty of room for eating things just for taste.