Not being in ember mode is a punishment, especially since they are much less common than humanity was. You lose the 30% hp bonus and can't get invaded by NPC phantoms, and they drop weapons that can't be acquired any other way. You can coop or invade to get them, but fuck that--I am not spoiling my experience by doing that shit. If I can't find an offline farmable source of them soon I'm going to be pretty annoyed with this game, because once you kill an area boss you can no longer be invaded, just like in the previous Souls.