Dave you don't know how many times he has disconnected his battery terminals, or connected them back up. It's not just a case of a one off when you connect your controller initially, it has the potential of this happening every time you connect the battery, which will be as many times as you use a charger. Yes it will cost money, the price of a fuse. It wouldn't need to cost anymore to add a fuse, and it would make the controller more desirable.