Then it'll be a grenade spam.... well.. more than what it already is.
You also get Free Grenades from Common Loot.
I am not saying that these ideas have no merit (and this should be here)
However, one must understand that not all "Good ideas" are actually "Essential" or "Needed". There is also the consideration of balance, development schedule, and what not. Maybe in the future. But not as something that is needed in the immediate future.