2012 Civic "Spoiler Fender"

[gdaybruce]

My daily is a 2012 Civic 1.8 EX. It's unassuming and easy to live with. A little while ago I noticed that a neighbour's similar car had little aero vanes positioned at the rear corners and running between the bumper and the rear light clusters - see: https://www.coxmotorparts.co.uk/honda-shop/genuine... This discovery prompted me to look closely at every other Civic I came across and while many seem to have these vanes (or 'spoiler fenders' as they are described in the link), plenty more are like mine and don't have them.

So, does anyone know which versions of the Civic had them and what their purpose is? They remind me a bit of the original Ford Sierra which had something similar fitted to the C pillar to improve stability in side winds so perhaps that's what these are for. Not the most important question of the day but I'm curious!