I'm sorry you didn't enjoy yourself. It seems to me that the server could have handled things a bit better.
However, regarding the beer temperature issue, I'd love to know what beer you ordered. Some are meant to be served warmer than others. Their hand-pull is also usually warmer than the rest. The only time you serve beer (or wine for that matter) truly cold is when you're trying to hide something. Cooler, but not cold, temperatures are reserved for lighter whites, lagers, some of the lighter more citrus-driven IPA's.
However, many European countries (especially Germany) serve their beer warm regardless of the style. Since Bank Street is trying to embrace this European sensibility, their beers will probably be warmer than what you'll find at other places around town.
I hope that helps assuage some of your shock at the warm beer, but I'm fairly certain it wasn't an accident. I don't know how busy it was or how harried your server was, but maybe a thorough explanation would have improved your experience.
"If more of us valued food and cheer and song above hoarded gold, it would be a merrier world."--J.R.R. Tolkien