Took off a rear brake drum to have a look at the state of wear. The car has about 120000km on it with all original rear brakes. The linings have about 70% of their original thickness.
If I take the previous wear and calculate how long they would last, it comes to a theoretical value of 400000km with the original linings.
Here the picture of the rear brakes on this 2014 car with 120000km. Some of the dust was brushed off with a soft paint brush prior to taking the picture, no brake cleaner used.