There’s two points in this post, one that is relatively conventional and one that isn’t. If you already know about the high cost of parking, skip to the second one.
So first, parking lots are actually quite expensive. There is the cost of the land, the cost to build them, and then the maintenance cost, which is at least $500 USD per surface parking spot annually. But more importantly, there is also the opportunity cost of what is not in the place of the parking lot: commercial use, retail, residential, public space, anything. By spreading out destinations with asphalt padding, various uses take more space than they inherently need. Most deleterious, however, is likely the social and urban form ramifications of mandated free parking (whether through by-laws or culture). Free parking is part of the larger equation that makes driving very attractive by making most its costs invisible, and it is one of the major building blocks of the sprawl of post-war North America. This high cost of free parking has been written about extensively.
But, in a slightly sinister way, parking lots can be worth more than even the New Urbanist might think. In particular, it may be worthwhile to sometimes let parking lots win against proposed downtown development — especially if that development is not of a high caliber. Once a development or park or any such use is in place, it will be there for decades. Parking lots, on the other hand, are an excellent placeholder (just don’t tell their owners). I think cities may soon be getting caught up in a rush to urbanize, intensify their downtowns, and all that jazz, but in the process may allow too many subpar developments and uses of space. They might also miss out on some uses, such as for public spaces like squares and parks, playgrounds, schools, train stations, or anything that wasn’t easily planned for with the current mindset. When cities realize their missing uses, they would do well to have a strategic stash of parking lots to sacrifice instead of needing to tear down something more substantial.
The recently opened public square in the heart of Uptown Waterloo is a good example. If that parking lot had not been there, a public space in such a central area would have been infeasible to obtain. Development is not always better than a parking lot, because the latter retains possibilities that the former shuts out.