That is not in line with the USB design goals. To quote from http://en.wikipedia.org/wiki/U.....Serial_Bus
"The standard connectors were deliberately intended to enforce the directed topology of a USB network: type A connectors on host devices that supply power and type B connectors on target devices that receive power. This prevents users from accidentally connecting two USB power supplies to each other, which could lead to dangerously high currents, circuit failures, or even fire."
I was surprised too when I saw the cable that came with the enclosure and the standard is surely very well designed in not allowing two hosts to be connected together unintentionally.
On the other hand, if model A could be configured to act as an USB device, I personally would have no problems using it like one, even if that would mean using a non standard cable.