Always glad to entertain you.

Apropos of your claim above that
plating costs a lot more, requires more steps, these steps require more caustic chemicals, and takes longer than modern paint processes
another question came to mind: If that's the case, how come I can get a chrome-plated tailpipe for my car for ten bucks or so?
WOW! You keep digging a hole for yourself! What you fail to realize is that if you compare it to the material and production costs of powdercoating, mass-production powdercoating is actually much easier and less costly! You also eliminate the cost of having to have two entirely different finishing processes for your product!
For most reasonably intelligent people, when they find themselves in a hole, they
stop digging! Clearly, you're still digging!!
It's only you who pretend to know things without a credible source to back up your claim. As I pointed out above, I assumed the "silver" version of the E-M5 was plated. You assumed it was painted. Neither of us know for sure at this stage, although you are of course free to pretend that you do.
Keep digging a hole for yourself! The reality is that modern-day paint application is pretty much the uniform and consistent manufacturing process used throughout the industry, not only for cameras but for plenty of other electronic devices. And it simply defies economic logic for Olympus to set up two entirely different finishing processes just so they can have one body in silver color and one body in black color! It's ridiculous to even propose your scenario, in fact. Suggest that to any production engineer and they'll just laugh in your face! They'll just say, "Uh, why can't we just use the same process for both, and just use different paint?"
When Hasselblad decided to offer a limited edition Ferrari-branded H4D, do you think they
plated it a different color? No! They
painted it a different color!
And when Pentax decided to offer a limited edition silver K-5, do you think they
plated it a different color? No! They
painted it a different color!
Likewise, when Olympus decided they wanted to offer the E-M5 in two different colors, they
painted the bodies in two different colors! That's how things are done these days. A simple, efficient, cost effective, uniform process for both bodies.