I have a 2008 Audi A4 TDi which was recently serviced at my local Audi dealership and I was told that the front brake pads would soon need replacing. The warning light has now come on, so I phoned the dealership to arrange for new pads to be fitted. I was informed that it is now Audi policy to replace discs at the same time as pads, regardless of wear. Is there any sound reason for this, or is it just a means of extracting more money from their customers?