Why ever not? The bits that get the routine service are bog standard Ford, are they not? Nothing exotic in any way. And the rest of the car is far simpler than most modern cars.
As for not checking the gearbox oil level, is it not filled for life as most modern cars are? Our family Merc certainly is.
I dont think that the owners willingness to pay inflated dealer service charges is any real guide to the state of the car.