More normally the customer gets phoned and told all their tyres are dangerously worn and need to be urgently replaced at £150 each, even when there is over 4mm tread left and the exact same tyre can be had for £100.
Exactly correct.
I got a call from my local dealer while the car was in for a service telling me that the brake pads were low and asking if I wanted them changed. I check these things myself and told the woman the pads were not low and to just do the work I'd asked for. I don't think the pads were even half worn! It was years before they were changed.
You expect this sort of crap from Quick Fit but it really is shameful that dealers do it too. And they do it all the time. Most people will have no idea how worn their brake pads are so will pay hundreds for work that does not need done.