Minifigures blind boxes question

So I recently sent an email to lego where I enquired about the blind box system for the lego minifigures. I found it a bit strange because I had heard on reddit that lego store employees permit the use of those apps that scan those QR codes on the bottom of the packs so that you know which one is inside. I will add that I am in full support of such apps as it takes the stress away from these things. I got even more confused when their email reply got back to me and said that store employees are NOT meant to help with this kind of thing [only one time I had heard of some employee covering those QR codes in a store], so is this an unofficial thing or is there something else going on?