I can sit down and craft for ten minutes, get up to tend to RL for ten minutes, then sit back down and resume crafting immediately.
I can run a dungeon for whatever relic part I've gotten to when the time opens up for me, whether that's 4 pm, 7 pm, or 1 am. Same for leveling.
Raiding has a set-in-stone time several evenings of every week that MUST be dedicated to the game no matter what demands the real world has of me.
That's the difference. Does a given player spend a lot of time in the game? Sure. Does that player necessarily spend time in the game at the usual raid times? No.
