the story is that the original alloys were of a softer compound, and Audi finaly admitted this after sevral compalnts and many bent alloys they gave all owners free alloys for the life of the car, and sent an ammendment to the owners manual which you should have in your manual but they also offered harder alloys to all owners which some took and they only have a 2 year warranty so i would check up from who you bought the car, which option the took.
i've kept the soft alloy's and have only had to replace 2 front ones due to pot holes but you've realy got to hit the hole with quit a force to bend the wheel and as long as it dosen't look like you've curbed the alloys Audi will replace them under the goodwill warranty. If your still unsure i'll send a copy of the warranty to you