Very true, they can be expensive to service.

That heated seat with built in massager costs the same $1000 whether the car is new and worth $100,000 or whether it is 10-15 years old and worth $10,000. At $100,000 it is 1% of the cars value and makes sense to replace, not to mention the fact that $1000 isn't as big of a hit to the bank account of someone who can afford a $100,000 car, versus when the car is worth $10,000 and the $1,000 seat is worth 10% of the cars value.

And many people know that if you keep up on preventative maintenance that the odds of stuff going wrong in the first place is decreased drastically.

Personally, I'd be happy with paying $1,000 to fix a part on a nice car that I've saved $89,000 on by buying used, hypothetically speaking anyways.