Yes, main dealers will always try to screw you over in my experience.
I've been the victim od the same thing myself on two occasions recently, The first was when I took the MX5 into a Mazda main agent for a service, purely to keep the service records up to date and let them do the first MOT before selling it. (and to have the roof looked at but that was another story). I do all my own work on my cars & bikes, very rarely letting anyone else fiddle with them unless absolutely necessary, so I'm always pretty well clued up on what level of wear most things are at. I went to pick it up and was told it needed new discs and pads - it had passed the MOT but was borderline....apparently! And, did I want to book it in to have it done? The car had just 11k miles on it and I'd had the wheels off just a few days before for cleaning (yes I'm that sad, I take my wheels off to clean them - ok?

)'. I checked the pads at the time and found they were less than 50% worn, and the discs were pretty much perfect, very slight lip but negligible - certainly nowhere near needing replacement.
Second time was in Nov when I took the bike into BMW to have a recall done on the fuel pump. It had just been recently serviced - by me so the service light was still on as I don't have the gizmo to reset it, it doesn't bother me so I leave it, it's been on for about 2 years at least now. It had also just passed an MOT a month or so before. I went back to pick it up only to be told, "It's way overdue a service sir, the service light is on and the oil is filthy, there's also some play in the rear axle bearings and your brake pads need replacement" I pointed out that I service the bike myself and do all my own repairs because I wouldn't let their team of ham fisted monkeys anywhere near it. I mentioned that it was interesting all those things were wrong with it because it had recently been serviced, and the MOT hadn't picked up any problems with either pads or the rear axle, not even an advisory! I invited him to come outside to where the bike was parked to show me the "filthy" oil, and the other things ....... He declined my offer.
Main Dealers, I wouldn't take anything to any of them ever again. Find a good indy that you can trust every time.