Do manufacturers really care about the 2nd, 3rd+ owners anyway.
Of course they do. Why wouldn't they? There are loads of reasons why manufacturers care about second and third owners. Here is a sample:
Strong used demand supports residuals, which encourages more new car purchases and enables better deals for new car customers. The more cars are purchased on finance the more important this becomes - the reason so many people can take a new car on finance is because the deals are supported by good residuals. Without second and third owners there are no residuals. A
Positive used car experiences reinforce a brands reputation - everyone knows Toyota means reliability, right? This reputation was not forged from year old cars that didn't go wrong.
Second and third owners are a source of aftermarket revenue - you can sell them approved used cars, you can sell them manufacturer backed insurance products and you can sell them parts and accessories.
A car manufacturer with a reputation for building cars which fall to bits after the warranty expires would find it more difficult to sell new cars.
people with a history of buying used cars and suddenly buying new are also in the minority.
You cannot seriously believe this. Virtually every single new car buyer was once a used car buyer. The number of people who order a brand new car as their first car and never buy used again are the ones in the minority. Many peoples views of the brands they want to own are based at least in part from prior experience. This forum alone is a classic example, look at the number of people here who have gone through the journey of buying increasingly newer second hand cars until they eventually become new buyers, ordering new cars from the manufacturers they've grown to like and trust through previous experiences.
My partner is a case in point - the first car she bought herself was a used Mini as the second owner. She really liked the car. Her next car was a factory order for a brand new one. I'd imagine the next one will be as well. If the manufacturer hadn't cared about second owners and hadn't offered a manufacturer backed approved used scheme, warranty services and service options for second and third owners I doubt her experience would have been the positive one it was which directly led to a new car order.
I really am quite surprised that you can't see that this happens all the time.