Ignoring all the complaining and false rumors that one must prove to be Haredi to be allowed to use the cheaper mehadrin online store (though like most online supermarkets one can only qualify if one lives within the delivery range of the store and the mehadrin one mostly only delivers in certain mostly religious areas), one aspect of this peaked my interest.

One might justify this by suggesting that the mehadrin version might be cheaper because it is lower quality or less healthy and packed with sugars (for food items) or whatnot. That is not the case. According to the report, 2/3 of the products are the exact same product with the same barcode - just one sold in the mehadrin store and the other sold in the regular store.

Does this put to end the assumption that having a mehadrin hechsher, or multiple such hechshers, causes products to be more expensive? Here it is specifically the mehadrin products that are cheaper!

It is possible that it is cheaper because they are taking less profit per item to leverage the buying power of the Haredi community that is often buying in bulk so they are taking lower profits per item but banking on selling more items. Even if this is the case it means the mehadrin hechsher does not necessarily need to cause a product to be more expensive. There must be enough leeway for the seller to still make it cheaper should he want to. A store might have a few loss leaders to get people to buy, but they dont make most of the store into loss leaders...