Agreed. I'm thinking this isn't a warehouse at BGT, but rather Intamin's manufacturing plant here in the states (unsure of its exact location). While I don't know much about Intamin's installation process, B&M track is (I believe) always painted before it is shipped. Judging by the fact that these track pieces are still in a bit of a gritty condition (look at those joints) and construction at BGT hasn't even gone vertical yet (many supports would be installed before any track), this is most likely a manufacturing plant and not the final color.
I suppose BGT could want to paint the track in-house, but look at pictures of fresh B&M track from the Ohio plant (occasional pictures can be found on Screamscape). It's always beautiful and glossy. Even a black color would have a great shine. This is just track pieces completely welded. Anyone with coaster knowledge would recognize the Intamin quad-rail track. It's for teasing, not final presentation. It's not uncommon in the least for park representatives to visit their "baby" being assembled at the plant. :blank: