Do you mean tiffin (as in the vertically stacked steel lunchboxes) or thali, the small, shallow bowls containing various dal, etc., all arranged on a steel dish? I don't think I've ever seen tiffin in this area. Do tell us if you track a source down!
The tiffin I saw at guru were the vertically stacked lunch boxes. As I said, looked too nice to leave at a random office, but might have been for special clients, the way some folks leave chopsticks at their favorite sushi bar? Next time I'm there I'll ask him.