Since douche bags make up 90% of the population, they're everywhere you go, even if you spring for the expensive seats, avoid public transportation and don't frequent sports bars. Douche bags are easily identified as they speak at higher volumes, use terms like "take a leak" and love to talk about everyone else's supposed homosexuality.
A douche bags enjoys a lot of attention and a large audience, so be sure to avoid eye contact and suppress any natural reaction you have to throttle him. Even if he doesn't end up bloody, you've won.