An electronic funds transfer system —- called E. F. T. in banking circles — is replacing the paperwork in banking processes. With its use of computers to carry out financial transactions, E. F. T. is changing the way people pay bills and may eliminate the necessity for carrying cash. But there is a snag in this technological revolution, and that is the reluctance of consumers to change their habits. Regardless of whether or not consumers like it, bankers are determined to fully implement the new system. The full use of E. F. T. nevertheless may be a quarter century away.