Whether you want to solo quests, explore fantasy lands, or do various versions of PvP, you always have the choice between MMORPGs and other games. From games like Dragon Age: Origins to Team Fortress 2, the various different gameplay modes of MMORPGs also exist in smaller games, which focus on just one pure aspect. If you just like one mode of gameplay, you can play such a specialized game and avoid monthly fees. All except for raiding: There is no game that offers raiding that isn't a MMORPG, which means you not only have to pay monthly fees, you also have to level up through modes of gameplay you might not like so much only to get access to the raid endgame.
Why is that so? Why is there no pure raiding game without a persistent world?