Reminds me of a story I heard from someone who went to ATS for a new tyre. Got it done and then told that the car needed new discs and pads on the fronts (was a front tyre that needed replacing) due to excesive wear on them.
He answer was 'I do not think so'
Reply 'Yes they are near the minimum'
'Can not be as they were replaced at the dealers 1 month ago and its only done 200miles since then'
He only paid for a tyre.
A tip I use when getting a car serviced is to mark the parts to be changed with an ultraviolet pen in a hidden type place. Then when rung to say its ready to collect go to the reception, sit and read the reciept with all the work carried out and then ask to see the car before paying.
Then, in full view of the reception, look at all the parts changed with the relevant torch. If the maqrks are gone then you know they have done the job, if they are still there then you know somethings screwy. I always say that I want to see all the replaced parts before paying the bill. Means I can check to see if the mark is on them as well.
Have got a free service this way as I made a complaint as they had not replaced 3 of the parts on a service but asked me to pay for it. Having the office full of potental new buyers/service customers worked very well.