Comment by Ajedi32 | Hacker News Reader

Comment by Ajedi32 | Hacker News Reader

Interesting argument.

> In 1941, your kid might have walked 15 minutes to the neighborhood school. In 2021, you drive your kid 15 minutes to school. Oh, and this isn't your choice: they tore down the old school and replaced it with a parking lot.

> In 1961, you might have biked or driven a few blocks to a corner store for milk and eggs. In 2021, you drive 3 miles to Kroger for milk and eggs, and there is no corner store. Has your utility increased? Or are you mostly just consuming more resources?

I would argue that utility _has_ increased; It's just that the market has re-organized itself such that the increased utility comes in the form of more flexible locations for houses and businesses rather than in the form of decreased commute times. One grocery store every 5 miles costs far less to maintain than 100 corner stores distributed evenly throughout the city, and you can get more house per dollar buying a house in the suburbs rather than if everyone were competing to buy housing smack-dab in the middle of a city.

I think perhaps a stronger version of the author's argument would be to point out that road use is an externality. Building more efficient roads comes at a significant cost, but road users don't pay that cost in a manner proportional to their use of those roads. Therefore the market does not factor in road construction costs when deciding how to organize cities, only costs of the transportation itself like commute times and gas usage.

I dislike the term "induced demand" for the same reason the author gave. "Induced demand" is really just "demand"; all economic systems work that way. The only thing different about roads is that our current system of road construction funded primarily by income taxes makes road use an externality.

> One grocery store every 5 miles costs far less to maintain than 100 corner stores distributed evenly throughout the city.

I'm not at all convinced that this is true. It would make sense in a vacuum, but there are a lot of negatives from the road infrastructure necessary for large driving-only grocery stores.

Dense cities have lots of smaller grocery stores rather than a few large ones. I'm sure there's a reason for that.

> Dense cities have lots of smaller grocery stores rather than a few large ones.

Hm? In my experience, dense cities have lots of smaller grocery stores, and they also have lots of gargantuan grocery stores.

In San Francisco, as far as I can tell, there are lots of small grocery stores, a fair number of medium sized ones (Trader Joe etc), one big one (Costco), and no really gargantuan ones. Maybe I'm not shopping in the right places though.

San Francisco is not what I would describe as a "dense city".

It does appear to be true that grocery store availability in San Francisco is just a straight downgrade from what you can find in e.g. much of the rest of the Bay Area. But that's a choice by San Francisco, not some truth about cities.

I can't think of a single big grocery store in Manhattan, the densest city in America.

In Berlin there are probably only a handful, and they're not in the city center.

There's a Costco in Manhattan

There's a Kaufland at Alexanderplatz in Berlin.

And it’s a great mix. I can do 99% of my shopping for food and liquor at the corner store. When I need to buy for a huge dinner party, or find some rare ingredient/bottle, I can ride a few miles on my bike to the larger store.

Okay, maybe dense cities were a bad example. Obviously density makes a larger number of stores per square mile more viable than it would be in a less dense area, even if you have a highly effective transportation system. My point though is that, all factors considered, our current city layout actually is close to optimal under the assumption that road construction is free.

The problem of course being that road construction is _not_ free; we've just created an incentive structure that causes the market to behave as it it were.

Based on what I've read, it's not that road construction is expensive, it's that ongoing maintenance of roads and connected utilities is quite expensive.

A grocery store every 5 mile costs a ton of fuel to maintain as clients need to drive in. It requires much more roads to be built and bigger ones too. It's not clear at all that it's more efficient when considering the whole picture

Induced demand is literally just latent demand that wasn't met and latent demand that wasn't met is just demand.

The only difference is the appearance that the demand is truly endless. Building roads is a subsidy to cars. People don't pay for the roads they get for free. The optimal strategy becomes driving because public transport is "inconvenient" because the alternative to bad public transport isn't better public transport, it's more cars. So, now the entire city wants to drive. Of course, the problem with that is that cars are such an inefficient means of transport that it's impossible for everyone to drive. The fairy tale of induced demand is born.

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