After much lively debate it was agreed that if, in the process of acquiring their other supplies, they had a chance to take frag grenades they would do so. That didn't mean they would definitely take the grenades with them on the mission, though. They could, Lupin said, make a decision about that closer to the mission after weighing up all other options. It went without saying that they wouldn't use the grenades against the goblins even if they did take them on the mission – they would be targeted at Death Eaters only.