You're right. It's not like every weekend the wife and I visit the capital building. But on the other hand we do hop on the metro every weekend and get off at one of 6 stops and find some new restaurant or wine bar. Each stop, from DuPont Circle, to Bethesda, to Adams Morgan, to Chinatown/MetroCenter, etc, etc, have more to do than I've ever done in Buffalo.
Outside of that, the several (a dozen or more) Smithsonian museums are something that you could do once a month or more for certain.
I'm not arguing with the points made by folks like Gordio, but he admittedly says CULTURE is not something he's into. For me, that's way more than museums and art. It's being able to hop on the metro, find a hundred year old bar that serves the worlds best tater tots hand made every week by one woman (yes, tater tots) and the next week be able to eat a steak made by one of the best chefs in the country, and the next week go to the Spy Museum. Now, DC is unique, but most big cities allow you to experience more than buffalo does.
And the one thing I cannot STAND, and in not sure this applies to anyone here, is those that market buffalo as one of the greatest cities ever, yet have never lived anywhere else. My sisters are a prime example of this.