A: Apparently in Japan. I visited last week, went to a Beer Festival, and was brought to a package store that sold it by the local homebrewers group.
I bought a brick for list price, ¥8400 (plus the additional $ conversion and tax). They had two more boxes sitting there.
The festival was just as exciting! Lots of Japanese beers and an awesome Japanese mead. (Yokohama Winter Beer Bash 2013
I can't compare it to a US festival (having never been), but I imagine it was more intimate and less crowded, but with much less beer.