Guild Wars 2

I was in World Vs World today.
My mind was blown.
I killed the Overgrown Grub with a few people – few to begin with, 20+ towards the end.
I was rewarded with 40k experience. 1k karma. 6(?)silver.

… For an Overgrown Grub that poses no threat to anyone, and really doesn’t have any impact on the world. No-one cares whether it’s alive or not.
1K karma.

How is 1k karma not the reward for the priest’s of Orr, and the Claw of Jormag?
Why are we rewarded with 380 karma for “saving an entire zone”, but rewarded with 1k karma for smashing a worm to smithereens?

Please tell me this is a bug, and the endgame boss-events were meant to award you the same reward as you get from killing the worm.

Originally DE’s use to give around 3k to 4k karma but they quickly nerfed it saying it was due to bots however i don’t see how lowering doesn’t encourage botting.

I really hope this is a bug. I expect to be rewarded with 1000 karma for destroying a priest who controls a statue throughout all of Orr, making it harder for the pact to advance.

I don’t expect to be rewarded with 1000 karma for killing a grub.

Is anything bought with karma tradable?