MMOs are, in many ways, the cradle of live service games—the place where the model we all know and loathe got its start. They have, in turn, tried to adopt some of the live service models that have proven to be the most popular, such as seasonal structures and, in some cases, battle passes.
Sometimes it works out well! For instance, WoW has a battle pass-esque system in the Trading Post, but it's completely free, encouraging players to do a bunch of activities in-game to earn some bonus cosmetics. In others, not so much.
