Rerouting Arduino's USB Connector to other Pins for a different purpose ?

I'm sure there is some sensible reason why a standard USB connector is used for a non-USB purpose but I can't for the life of me understand why a much simpler connection is not made direct to pins 4 and 5 with some "DuPont" connectors.

At some time in the future someone is going to connect a standard USB cable to that socket and to a PC - it may even be the OP.

...R