Finding excuses to charge money on fund unavailability.

I work in the software industry. If data is unavailable, I don't see how that would cost anything to the system. Yet FNB finds the excuses, failed transactions and failed debit orders to penalize customers. For me this has absolutely no rationale except the fact that the few banks monopolize the market, hence South African consumers have no choice but to allow banks to rip them off. I have had the chance to travel abroad and FNB is very unfair in their greedy ways of milking consumers.