i got my last car and in the ad it said back seats never sat in....
car is a few years old and there were scuff marks on the centre console in the rear where it had been worn, clearly by shoes. it didn't put me off as the actual seats are unmarked.
then again, i traded in a car with only a part BMWSH without the book with stamps but did provide evidence through BMW helpline and they sold it as full service history.
people will say almost anything they think will help sell a car these days.