I suspect bread crumbs a century or two ago were likely better for a chick than what someone might buy at the store and use today.A century or two ago, bread crumbs and hard boiled egg probably was one of the best possible chick foods (compared to what else was available at the time). But something is only "best" until something better comes along, like modern chick starter.
Also, just saw the post that said the suggestion was for day one, hen would have them out eating regular "wild" chicken food soon. I agree.