I think the marketing works because it gives you just one option that everyone automatically uses. I just downloaded a 5th messaging app from the Play Store because everyone uses something different. It is exhausting. This is one case I hate having "choices" among 100s of mediocre apps.
Cars don't come with a guarantee that it will last until you're 80 though. You go over a certain mileage, you're counting down the life of your car.
On the other hand, marriage is touted as this perfect "till death do us apart" deal.
Should weddings be sold like cars? With "your mileage may vary" and "you will have many marriages throughout your life?" Maybe then I'd agree with your logic.