This is, most likely, the single thing I miss the most about my days in new York: Bars are lonely in buenos aires! And by bar, I mean the actual bars where in new york you go and sit, and talk to people because most of them are there by themselves anyway.
Here, even when you go to a place that has people sitting at the bar, they are usually couples and are not open to conversation.
Not that I am complaining, but I do think that having a social custom of interacting with similar people at bars is good for business. Can't prove it factually, but something in me tells me that like-minded people talking at bars are always good. (except, maybe, for match.com or eharmony, hehe).
Cheers!