Bread is always best made fresh like that. The freezer helps extend shelf life at home.
You mentioned calcium propionate as a preservative. You also mentioned butter. Calcium propionate occurs naturally in butter. Cheese as well. It's "generally recognized as safe" but of course also has nasty side effects. It's possible people buttering their store bought well preserved bread concoction are ingesting far too much. They add the stuff to the bread at a level they think is safe, but maybe don't account for what the consumer adds to their bread once they get it home. That preservative is also in some sandwich meats. People are eating that stuff in layers...
Bread never lasts long enough with me for the freezer yet lol
Good information as well! They say that about many things that it's safe in the amount of what's in the product but I doubt they account for all the other things people consume in the day resulting in I would think many unsafe levels.