The Beer Mile, or any of the other drinking-and-running events out there are no joke if you're a competitive person. It was at one of this type of event that I learned I can/could chug Guinness like a champ and still run at a decent pace. Regular beer like Coors or Bud, no chance. I'll be giving it back in about five steps, if I'm lucky.
That said, most people who participate in these, are simply out there to have fun, move about and drink some beer. The less seriously you take it, the more fun you have!
Personally, I prefer to have my beer at the end of a run/jog/walk than in the middle. But sometimes, on a long run, a shot in the middle is fun!