Should have just kept the cases to skins. Ifrit skins, hunter skins, heli skins, w/e.. people would have still tried to get them. Also everyone who buys crates now is missing out on future items they're going to add to the crates as said previously and will be pissed off when they give everyone the coveralls anyways because of their advantage.
The only reason the coveralls are expensive to purchase in game even after you've unlocked them is because they give an advantage. If it was TRULY cosmetic they'd be as cheap as all the other clothing.