Contrary to art to order, which serves, commercial art tries to guess what the customer may desire, while ideological art tries to impose on people what they should wish and how they should think. Both, then, are looking for a recipe which they will not find because there is not and there never will be art from a recipe. Commercial art is a lesser art, halfway between art and craft. Therefore good commercial art must be technically irreproachable, a requirement that doesn't apply too strongly to art. Of course religion can become political, so the art expressing it becomes commercial.
Eroticism can be commercial, so the art expressing it becomes pornography.
Even rebellion can become a caricature of itself with kitschy art as its expression. I was talking about authentic religion, rebellion, eroticism, in contrast to politics or any other profit oriented policy or philosophy like marketing, trading, etc. At this point the conversation ended.