In some places like Turkey, shops traditionally keep a "debt book" where customers will accumulate debt for their purchases and pay once they have the money. Wi

In some places like Turkey, shops traditionally keep a "debt book" where customers will accumulate debt for their purchases and pay once they have the money. With the prevalent use of credit cards the tradition is much less widespread today of course but it is still used by people who become unbanked for one reason or another(i.e. people who are persecuted, people who went bankrupt and want to keep their transactions out of books). So, no, loss of connection or system break down won't necessarily mean that the trade stops. People have many ways of issuing IOUs and they can go creative.