I don't see a lot about laws and taxes in here. Excise tax is lower than most places. Real estate is limited, which plays a big factor. There are tons of bars in DC, so I don't think it's any harder to get zoning and a liquor license than any other city.
I think the biggest takeaway here is that DC is damn expensive. And moreso, a place like San Fran has a high cost of living but beer aficionados know what the product should cost. DC is full of trend followers so anything that becomes suddenly popular is going to skyrocket in price. Clueless consumers get what they deserve.