I don't think this question has any clear answer, because of the way that credit cards evolved. Businesses commonly provided products to their customers by recording the transactions in a ledger. The customer would come in every week or every payday and pay off their balance or as much of it as they could afford. The small-town grocery store that my sister uses still offers such a service to customers who they get to know. At some point, someone had the idea of offering clients some form of credit to assist them in purchasing products they needed or wanted. Credit probably came about first for those on the lower rungs of the economic ladder, because they had trouble affording any kind of large purchase. It was quite common for people to purchase their furniture, for example, on credit with the store that sold the items. A certain amount would be paid to the store every week or payday, usually with interest added. There were also businesses that specialized in offering goods for sale on credit. At some point, this process became more formalized when large stores realized the potential of the system and began to create their own credit departments. It was probably inevitable that, with a large number of customers purchasing on credit and the risk of having one customer's name confused with another's, that accounts began to be associated with a number rather than a name. There was one advantage with issuing your own credit accounts: the customer would be more likely to shop with you again if he or she already had an account. This became a common way to purchase many items, including gas for the family car - most producers issued their own credit cards at one time. They still do, but usually only for commercial clients. This was fine for large stores, but smaller businesses had to maintain their own records and extend credit by themselves. This could be a strain for a small business and many fail because of non-payment of debts. People were already in the habit of using credit at large stores, along with borrowing money from banks and lending companies to finance the remainder of their household needs. This led to the develoment of the modern credit card system, which is pervasive in today's society. We still use credit for the same purchases our grandparents used it for, but we also use it to provide short-term loans for many items people would never have used credit for in the past. The major retailers have generally abandoned their own credit departments and now use the services of commercial credit card companies. And we still pay the interest, which is far higher today than it was in the past. Credit cards for almost everyone = increased risk of bad debts plus high interest charges to offset the losses. However, credit cards are extremely profitable for financial institutions.

sears department stores

edit: why didn't I see this was a very old question...