Cooking grenades is not a purchased ability, it is something any character can do from initial creation.
Being able to sprint while cooking is a low level ability, and grenade shooting is a high level ability. As some have surmised, slots are not a concern with passive abilities that don’t require d-pad activation.
And no, we don’t call them ‘perks’. 
:stroggtapir:
:stroggtapir: