The potions and scrolls come like that, so we have to identify them first, either by trial and error or using identification scrolls or stones. It's a mechanism to add some sort of realism and a greater challenge. Armor and weapons require using strength potions to properly use them. That last one I agree that isn't well done, because we get lots of scrolls to upgrade stuff, much earlier and in greater numbers than strength potions, so the new equipment we find usually aren't better than our upgraded stock ones and we need to carry them for a long time until being able to use.