I don't think "force damage" is necessarily something magical. It just means that things get pushed around when the powder/bomb expodes, like from real world gunpowder. From a real world bomb however you would expect piercing or bludgeoning damage from high velocity fragments though, but here they just choose to call it all "force damage". There may be a reason for that which become apparent later on when you find a use for the items beyond just blowing up enemies.
The smoke powder plays a role in the story. I can't say more in case I spoil it for others, but my advice: Hold on to those items until you find a real good use for them. And yes, smoke powder IS a game changer on the battle field, and I think is meant to be. Luckily I have not yet experienced bombs being used against me in combat, so not so worried about that just yet.
