Unlock progression. I get your point, it does not affect actual gameplay. However regardless of that fact, increasing the grind to unlock in game items in a full retail game to push people to spending extra real world money to aquire said items is a shady business practice.
To many players unlocking things is a sense of progression. In a game like BO4, it is the only progression you really have. If something gets locked behind a paywall or your progression is slowed in a game you payed full retail price for, it hinders the enjoyment of the game itself. If this were not the case, people would not be angry about it, but they are sooooo.....
You can play devil's advocate all you want on this, but it is never ok to lock content behind a paywall for a full retail game. If you think it is, and I mean this with all due respect, perhaps you are part of the problem. And I do not mean you as a person, but anyone who believes it is ok. You give these publishers an inch, and they will take a mile. That is why I will never be ok with micro transactions in a full retail game.