Rogues can now buy poisons from a vendor instead of having to mix them up themselves. Blizz didn’t want poisons and their reagents to clutter their bags.
Hunters can now stack a b-zillion arrows/bullets into one bag slot. Blizz doesn’t want ammunition to clutter their bags.
Warlocks can now gather soul stones whenever they use Drain Soul.. not just if it kills a mob. Blizz wanted to make sure our bags were bulged with soul stones even when we were wiping on boss for a whole night.
Hardly seems fair.