That's not playing the game, it's grinding for cash plain and simple. I'm not saying it's necessary grind, but it is there and it is what the majority of the PvE player base does.
I'd be fine with the current difficulty of PvE if there was more varied and interesting gameplay, but overall it's still really static. The dungeons don't vary, and the events around the world feel merely like public quests. For me, FotM is the thing that kept my attention to most simply because it had only an ounce of variety, and the fight mechanics within it were the most interesting.
Dark Souls is a game that I keep coming back to day after day simply because of all the mechanics providing replayability. With the intense difficulty, random (or constant, if you choose) PvP and co-op, and - most importantly - the millions of build possibilities, I have poored hundreds of hours into it. And that's all for it's PvE.
GW2 lacks a lot of that variety for me. While there are a handful of classes to choose from, I don't feel like I have as much choice over what to do with them as I'd like. Some of that is balance, the other is the structure of the game itself. This could've been overlooked if PvE was more challenging and varied, but as said, it doesn't change a whole lot, and isn't all that challenging.
Hence why I consider GW2 "grindy": When few things in the game feel rewarding, it feels like the only thing the game rewards me for is my time.