I'm pretty sure that actually that feature is for all. If you have joined the Guild USMC and you are currently even on another character playing with him (representing another guild or just roaming free), on the USMC roster you will appear "online" with the character you are on, and you can know if you are representing him or not. Unless they changed, but that was my experience in bwe1 and bwe2. I believe the reason for it was more like "Stay in touch with people". But I could be wrong.
Yeah, guild with "just represent us" are bound to be too tight, might even work but it's not for me. I feel like the community in gw2 is worth meddling with XD, so I was actually thinking of making my own guild to help people too, but I might do that after a few months of experience
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