I did. Maybe you should. He was trying to do "the right thing", but that still doesn't change that it was out of self-interest and that he wasn't really expecting to sacrifice himself. Is there any point you can make that would convince someone that Grom KNEW he was gonna die in the fight against Mannoroth, that he KNEW Mannoroth would blow up and take himself with him? No. He was just there to kill a demon. Just like he kills pigskins.
What Varian did was on a completely different scale. Thrall and Grom faced one demon, one that, under other circumstances, could be killed without any casualties (see WoD). Varian faced a Legion. The moment he gave Genn the letter to his son and dropped down from the ship he KNEW he was gonna die. He accepted death for what he wanted to achieve. Grom might've been prepared to die in every battle, but he never knew he was gonna die for sure. If you try to kill someone, and he takes you with him, that's not a sacrifice. That's more of a failure.
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It's actually in the Blood Oath of the Horde, that every member of the Horde takes.
http://www.wowhead.com/quest=11983/b...h-of-the-hordeLok'tar ogar! Victory or death - it is these words that bind me to the Horde. For they are the most sacred and fundamental of truths to any warrior of the Horde.
I give my flesh and blood freely to the Warchief. I am the instrument of my Warchief's desire. I am a weapon of my Warchief's command.
From this moment until the end of days I live and die - FOR THE HORDE!