My Building Official thinks the same way. The room is what the architech labeled it. He explained that the other codes he is responsible for enforcing must all look at a structure from the same position. Any change in use from the drawings is the owner's responsibility and should be resubmitted for plan review. So, if it walks like a duck and talks like a duck, and the drawing calls it a frog - it's a frog and the building department is not liable for any misuse by the owner. So, in your situation, I would say look at the drawings, if there is a change, then they have to be revised/resubmitted.