is a load of rubbish!
What does it even mean? Is it just an excuse for it to cost more money?
It looks to me like each item is hand picked for the feature store so rarity has nothing to do with it.
These items have rarity because originally they were all suppose to be in the loot tables. We were suppose to be getting vanity items as a regular part of the loot system. If a bad guy had a chance to drop an uncommon gun, he would also have a chance to drop an uncommon vinyl.