I'm out in San Diego for the road trip, and am simply bowled over by the wide availability and excellent selection of beer at Petco Park. Inside the park there are a couple of stands that focus on SD-area beer from Mission, Karl Strauss, Coronado, Ballast Point., and some carts with Kona, Widmer, and others. In fact, good beer locations seemed to outnumber spots for lesser beer. And as a bonus, the Mission Brewery tasting room is just across the parking lot from the stadium.
I sure wish Nats Park could get its act together--with the quality we have in the DMV, they could do far better.