But you know...not everything is bad. Taarof makes actual travel to Iran rather smooth and comfortable as people really try to help you the best they can (as long as you have at least a small sense of what is too much, which you get fast).
Joking, if it's like this and is not terribly linked to a religious dogma( which doesn't seem to be, more like a cultural thing), I'm sure there's a 'raison d'être'(I believe natural selection applies to not-directly-biology-linked entities such as societies). Maybe violent fights/discussions are more prevented thanks to Taroof? That's a wild guess ofc.