Why does DC have so few amenities?

Mr Brian Beutler says:

I cannot possibly fathom why D.C. lacks the number of book stores, record stores, coffee shops, night clubs, 24-hour restaurants, etc., etc. that you’d expect based on it’s relatively large population of wealthy, single young people. I love my D.C., but I’ve also found that San Francisco, Seattle, Philadelphia, New York City, Boston, and Chicago all have way, way more urban perks than Washington does.

To which Ryan Avent, DC development blogger extraordinaire, responds:

Now one potential explanation, and I very much could be wrong, is that Ezra and Brian generally confine their experiences to a limited area within D.C., and that area is one which has not had all that long to develop. That is, if you take into account other neighborhoods up Wisconsin and Connecticut Avenues that bloggers may not visit much, then you get more of these kinds of businesses. Another explanation is that some of the businesses you’d expect to find in D.C. are instead in Arlington (or Silver Spring or Alexandria). But I think the main issue is that the District has not been all that dense, residentially, for all that long (or rather it was, then it wasn’t, and now it is again). Many of the dense areas of the city were hardest hit by population loss during the city’s long downturn; much of the population that stayed lived in detached, single-family homes away from today’s popular core. Plus, since housing supply is slow to catch up to the number of people who now want to live in the core, housing isn’t cheap and shops skew toward a wealthier crowd.

Too, I think there's occasionally sample bias in what you visit when you don't live in a place. I love Philadelphia, and am pleased as punch about the comeback it's staged; it's a much different, much better place to live then it was when I arrived for my freshman year at Penn to find the campus plastered with warnings about the fatal shooting that had taken place a block from my dorm the previous night.

However, most of Philadelphia is like most of DC: vast stretches of row houses and other low-density housing served by precious little in the way of services, government or otherwise. A few years ago when I visited a friend living in one of the many ungentrified sections of South Philly, I was appalled to realize that the place* still had no public garbage cans, with the result that people walking on the street had turned any open receptacle, from washtubs to flower pots, into makeshift substitutes.

If you're visiting, however, unless you have really, really, poor friends you don't see that part. (The person I was visiting had was sharing an enormous two bedroom apartment that cost a little north of $400 a month.) You see the fun, crowded bits. But those bits are about the same size as, or perhaps a little smaller than, Adams Morgan/Dupont/Georgetown.

Obviously, that doesn't account for all the difference between DC and other places; they really are better economically developed than we are. But I think sample bias accounts for some of the invidious comparison. When I was visiting DC, I always had a great time going out, and always went to a different bar or club. I didn't realize that when I moved here, I would be going to those same six spots over and over and over again.

* This stretch of South Philly, I mean; not the whole city