There are several Billy Goat Tavern locations, including one in Washington D.C.!!
http://www.billygoattavern.com/home.htmlThe Billy Goat's original location was right near the Tribune building, and most of Tribune staff and reporters hung out there.
As an aside, almost all of those famous SNL stars who cut their teeth in comedy with Chicago's Second City comedy troupe (John and Jim Belushi, Dan Akroyd, Bill Murray, etc) all were rabid Cubs fans. I think it grew out of the the fact that Second City is a north side institution, and it was easy for the cast to attend day games at Wrigley Field and make thier evening performances.