Many times the competition forces companies into open accounts because the competition is doing it. There needs to be a balancing act between competition and security. Transfers credit risk from buyer's bank to confirming bank. A Trade Acceptance is a time draft drawn on a non-bank entity and accepted by that entity. A Banker's Acceptance is a time draft drawn on a bank and accepted by that bank.
Banks deal in documents.
Documents appearing on their face to be in order is all that is required. This is obviously not a substitute for a buyer knowing their seller.