Do all the RS6's have vented from fender wells? Or just the later models?

I thought this was odd since Snow and small stones get up into the engine bay!

Also, I first noticed the vents when I was investigating a strange sound which sounded just like a stone going through a metal grait! It was just that!

I suspect it's somewhere for the infamous "siren" fan to push engine bay heat to. Don;t think the brakes needed extra heating though...