There is absolutely nothing that is compulsory in this game, I don't know why you would think that.
Fury, unlike Crum, offers players the choice of world PvP, minis and access to all the PvE content at the same time.
Offering people the maximum amount of choice in how they play is always a good thing.
If you don't like PvE, that's fine, don't play it, but some people like to do everything.