I'm having trouble understanding why we haven't eliminated bank robbery as a possible crime opportunity?

While this method works in some cases, there is always the possibility of the inside job thing. Im sure this method can be very costly and the loss of thousand of dollars due to ink can get very spendy. Im sure there are a lot of thoughts into how to eliminate bank robbery with costing the bank to loose so much money. That money is no longer usable and that can create quit a loss.