Isn't that the colour it comes from the factory?
Very similar to what I see at Bunnings.
The power thing is pretty crook. I guess as its still the builder's site, you couldn't simply unplug anything. I guess you photographed everything in sight - that 'note' seems pretty damning. I'd be seeing the site super personally, with all the evidence and let him know that he's up for the power bill. He might call your bluff and not pay I guess ...
Police? You are right, it is theft, but I'd consider:
* The police reaction is likely to be "try to sort it out yourselves in the first instance"
* If it is the builder's site, and the site super gave permission, then I think the Police would find a way not to progress it.
But then again, per chance the bill turns out significant, then a police report would be a good back-up for any power company discussions.