a) Nobody knows other than Apple about whether the cost of building the SDKs etc are included in the price of the iPhone. So making definitive statements about their being no additional cost makes no sense.
b) Microsoft and Apple both charge for developer programs and in the past it used to be significantly higher than today. So there is a precedent for this.
Apple financial statements are public. We know the income from hardware sales exceeds all costs and R&D by far. The app store fees are basically stealing from society on top of that to enrich themselves.
b) Microsoft and Apple both charge for developer programs and in the past it used to be significantly higher than today. So there is a precedent for this.