It's not as if people can't afford to buy new ones it may be because they don't see the books on shop and store maybe those books are not in stock so I think if you have old books that are of interest to people you can still sell them and make alot of moneyActually there are several money making opportunities to which you can earned from sell used books or second hand books simply because there are alot.of people who can not afford to purchase the new ones so the will prefer to get the second hand books that the price will be less expensive for them.