This happened to me. The dealer rotated the tires at 5K mi. and never again.
At 42K mi. I noticed the inner front tire wear and rotated the tires. At 47K mi. a rear
wheel bearing was making noise. The dealer replaced it under warranty.

At 110K mi. the font wheels started vibrating at 45 mph. The tires were wearing
evenly. I had the tires ballanced. This didn't help. I had the tie rod ends replaced
and a 4 wheel alignment. This fixed the vibration.

Buy 2 new tires and rotate every 20K mi.

 

Tires get feathering from bad balance and toe problems in the allignment. Inner tire wear is caused by a negative camber problem, and outer tire wear is caused by too much positive camber. Too much tire wear on both outsides of the tire is cause by low inflation, and too much tire wear in the middle of the tire is caused by overinflation.
Audi recomends a certain amount of negative camber but not enough to cause tire wear like what you describe. You need an allignment. The dealership my not have the tool to move the subframe to correct the problem (if it is not an actual Audi dealer) or they may not want to mess with it because it is difficult to do and may not be able to be corrected. The alignment gets off in the first place because steering and suspention components bend or sag. you may have a bent strut rod, sagging spring(s), bent steering knuckle, bent control arms, bad bushings in any of these or a bent subframe. Most likely it is still something that can be fixed with just an alignment and the work involved is the reason the dealership sent you away.
Bad tires do not make other parts go bad. wheel bearing such as the bearings in an audi go bad because of overheating, inproper instalation, defective bearings, or normal wear and tear. If the audi dealer said the bearing went bad due to bad a bad tire, they were only lying to you to make you feel more comfortable able the automobiles they make.
The shop telling you they will align it for $80 most likely will not have the tools needed to correct camber issues unless they specialize in Audi's. Regaurdless, there is not a single car manufacturer in the world creating alignment specs that will prematurely wear out tires, awd or not.

 

Tires wear differently front and rear. Camber is set negative 0.58 degrees for front wheels.
This causes the inside of the tires to wear. Roads are crowned which adds to the inside wear.
There is more weight on the front tires adding to their wear.

 

i was told that too!