Grenades are generally used for two things. One: to draw an enemy out from cover into your sights which you can easily take them out unless they find more cover. Two: To get the cover of fire off of you while they scramble to get away from the grenade. If you get lucky they will get harmed in the blast and possibly killed. Impact grenades (Ones that explode on contact I don’t know the actual name unfortunatly) Are more used to take out a line of enemies quickly. Since it explodes upon impact it doesn’t give the enemy much time to get away if they don’t see it. If they see it coming from a distance however they will get away with minor injuries or no injuries at all.
Following that explanation, heres the short version. I would not be the ones to pick it up and throw it back. Theres never enough time to aim it right where I want it to go, and always explodes before it either leave my hand, or explodes in the air. So I just book it for the next available cover. shrugs