Q:
Guild bank gold limit, Why?
A:
Probably because a few guilds have given vault access to players that just clean them out and disappear. Unless the cap has been in place since release, then I dunno. But I imagine they’re just trying to limit the amount of damage a guild can do to themselves to not have to deal with related support tickets. I think that was their reasoning for the limited gem exchange feature as well, they want to make it harder for new/dense players to make mistakes so they don’t have to deal with them via support. But that’s just my speculation.
I think Skate’s point makes a lot of sense. It could be there to minimise losses if a thief accesses the guild bank.
Even if your guild is full of trust-worthy people, somebody could hack a guildie’s account and wipe the guild bank clean (and A-net won’t recover guild bank losses).