I'm searching for a short story I read probably around 20 years ago in a school anthology. It was set in a futuristic setting, where consumerism was rampant. The two protagonists were a door-to-door salesman and its customer.
In this futuristic setting a person could buy things with credit not only by indebting himself but also by indebting the first X years of his son's salary (this even when the son was a child... So you could buy a new TV by exchanging it with the first year of the future salary of your son, to make an example).
The customer was already quite heavily indebted (and clearly already had his house full of things he hadn't ever used, like a pool), and the salesman was trying to persuade the customer to indebt a little of his son's future salaries. If I remember correctly, the customer hadn't still indebted his son, and he was reluctant to do so, but he had already nearly tapped out all of his personal future salary. The salesman used at least two ways to persuade the customer:
he told him that anything he bought would then be used by his son, and a day would become his son's property (at the death of the customer), so it was OK to use the son's future salaries.
AND, big "secret", he told him that his neighbour had already indebted his yet-to-be-born niece. He told the customer that his company would have to invent new things to sell to this neighbour :-)