Mac mouse madness

One day last week I was in the office of a new colleague discussing a project. He uses some kind of Macbook, which sits on a little elevated platform next to a large external monitor. Part way through our meeting, the batteries for his wireless mouse died. He reached across his desk for a USB cable, and I fully expected him to plug it into the front of a mouse, in exactly the same position that the cable on a conventional wired mouse attaches to the mouse body, and continue using it while it charged. Instead, to my astonishment, he picked the mouse up, plugged the cable into its *underside*, propped it up on its side at a roughly 45 degree angle, and switched to using the Macbook's touchpad.

I was absolutely flabbergasted!

I'm very used to Apple manufacturing deliberately dysfunctional hardware in order to make more money selling solutions (e.g. many of their computers lack any and all standard I/O ports, so to get anything done you have to buy a fistfull of overpriced adapters, many of which will eventually be lost by people travelling with their computers, requiring them to buy more), but I just can't figure out what their angle is here with this bafflingly bad mouse design. Do they expect people to buy *two* mice and hot swap them? Is it some kind of weird internal joke, to see just how bad a product their marketing wizards can convince people to buy?