Why does my local dealership insist that brake discs are replaced at the same time as brake pads?

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?
Since asbestos was taken out of brake pads and replaced by metallic content, brake discs have been wearing items. But it depends how worn or how rusty they are. I see no grounds for automatic replacement.
Answered by Honest John on

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