Unpleasant attitude

Visited Foschini store at The Glen Mall on the 3rd of December, well the shop is clean and well organized except for the one other staff member who was rude towards me and my sister. I am not sure whether it is part of the rules of the shop or not but if it is surely, it should be written somewhere visible for everyone to see. So, I was taking a video and photos on the mirror in the shop, and I was told not to do that by one of the staff members, she did explain much beside ''you are not allowed to use the mirror.'' As shocked as I was, I tried to continue shopping however my mood was already ruined so I decided to leave the shop. Any reason why we are not allowed to use mirrors inside the shop, what purpose do these mirrors serve if we cannot use them?