This is the part I am a bit confused. Is brown boxes really that important?
Brown boxes were done for shipping purposes. I have noticed, HT's brown boxes are no longer shipping boxes but a protection for the original packaging. Therefore, they had to use another layer if shipping box.
EXO-6 brown boxes are intended for shipping. We used heavy paper stock and actually stronger than standard off the shelf shipping boxes. We know damages are usually the couriers problem. If we use another shipping box on top of the brown boxes than the cost will be significantly higher in shipping (dimensions and weight whichever is higher).
As long as you know you would not be regretting, then everything is fine.