Oh, you can grind it perfectly fine. All you need to do is find the zerg, pretend they're NPCs and sit next to them occasionally throwing in AoE to tag necessary stuff. Congratulations, you now know why botting is rampant in GW2 WvW. It makes no sense not to bot it. It's good income of gold and karma and actions of individual players and most squads are largely pointless in the large scheme of things. So just relax, turn on your favorite botting software and go do something fun while it grinds karma and gold for you for months.
In fact, that describes the entire game very well. The best way to get value out of GW2 is to simply treat everyone in the game as NPCs, including other players. The game is built on the assumption that you will do so by making communication all but pointless. The appropriate solution to most problems is to just zerg objectives with "N"PC zerg.
And of course, there's the whole pay to win aspect of the game, as you can effectively everything including the legendaries in the game by simply paying money to arenanet.