Tire Wear/Alignment issue
I have a 2013 C300 4Matic Sport (staggered setup, so no rotation, R17, 225/45 Front and 245/40 Rear tire) and it burn through rear tires really fast. The most I've gotten out of them has been ~15000-18000KM. I have
Michelin Pilot Sport A/S 3+. However, only rear tires wear so fast and front ones last almost 2 times more. A few mechanics have told me that this is normal and since 4Matic starts spinning from rear first, so it usually wears them faster.
Is this really true? How much other owners get out of their tires?
I also finally took it to a local recommended shop (in vancouver) for an alignment and they said the toe was off but the camber on rear ones is not adjustable. Is that true? and does any one know what's the recommenced values for Camber? Is there any point in taking it to the dealer mechanics?
I've attached my alignment readings before and after. The wear was really bad inside of rear tires, could the toe be the culprit?
Thanks
Alignment results:



