imo the point of throwing a potion bottle is so every character doesn't have to carry potions... and the point of that is so the players don't collect 200 potion bottles as they move around the map
as a game mechanic it lazzy but okey as a stopgap to keep things moving along... once you release the game its better to simply give the bad guys potions that break when they die like in BG1 and BG2
