There are some people who are lax about this mitzvah because they think that they are not the only people in the town and there others in town who have the ability to gives loans, including wealthy people. The truth is that this is not a correct argument because it could be that those other people do not want to help the fellow who is asking for the loan (for whatever reason). And even if the fellow has wealthy relatives but they are unwilling to help him, that does not exempt the other people in the town from giving him a loan. Furthermore, when a person has the ability to give another fellow a loan, he is not exempt from this mitzvah just because there are other people who are wealthier than he.