Because it's not that easy, unfortunately. The 5-way switch (d-pad with center button if you will), is molded into a shell. That shell is what sits in the cavity of the steering wheel. Even if you removed the switch from the shell, you still have to deal with the wiring inside, behind the switches and contacts, and the fact that the d-pad and the shell are formed in a way to only allow installation one way (as in there's notches or grooves that will only let the switch sit in the shell at the "correct" position).
Hope this makes sense. (I'm a former automotive technician turned training/warranty coordinator)