https://wiki.guildwars2.com/wiki/Box_of_WvW_Supplies
This is a pretty good item. It drops WvW relevant food, siege, gives WxP, and even gives really cool stuff like metabolic primers sometimes. I have gotten 7 metabolic primers that I would have not gotten any other way. As intended these items are supplies that could help you WvW. I like getting this from my Ley-Line converter for cheap, and the wxp is great for doing guild missions.
But where do you get this thing? Not WvW. Well, you could use the karmic converter, but that’s from an expensive achievement so I don’t count it. HoT Currency (Requires PvE), and Guild Commendations (Maybe WvW, but insanely overpriced).
So why not sell them for badges or Proofs for a discount, or put them in a reward track? These things would be great. Kinda makes sense that WvW should be the best place to get them.
For once you have tasted flight you will walk the earth with your eyes turned skywards,
for there you have been and there you will long to return.