Lol yeah, being down there in the darkness would be scary I think.
One thing I know is, these vaults are all connected to the clubs and pubs around town, so Iv heard from many people who work in these places and have to go down to change the beer etc that they sometimes hear noises from other venues, shouts, screams, clangs etc
I guess when its a "tourist attraction" in our home city, we think its not for us its for tourists and Im not a tourist so it would be embarrassing to see it. I am now certain I need to go to the vaults :)