They don't have no margin (i.e. nothing is 'at cost' as GP presumes), they just have very low margins which they make up for with high volume. It's not that no

They don't have no margin (i.e. nothing is 'at cost' as GP presumes), they just have very low margins which they make up for with high volume. It's not that novel, but Bezos has created a company with tolerance for lower margins.