The counter to that, however, is this: traditional urbanism existed long before "the corner store" as we conceive of it, and was/is able to accommodate changes in economic models at all scales, from individual retail formats (remember where the Department Store was born - traditional downtowns in the 1800's) to city- and regional scale shifts (New York, for example, wasn't always a center of fashion, entertainment, high-tech, international finance, etc.)
Traditional urbanism is an armature that is able to absorb all sorts of dynamics and change, and it is not dependent on any single business type. Therefore, I urge neighborhood advocates to not get wrapped around the axle of debate about a particular (largely by-gone, at least for the time being) urban component like the corner store, but rather to embrace urbanism as a system which can accommodate contemporary retail formats, as well as "nostalgic" ones, and future ones, which haven't been invented yet. One of the main ways urbanism is so resilient to these sorts of changes is because urban buildings (and blocks, streets, even neighborhoods and cities) can change function over time, absorbing the ebb and flow of, for example, the balance between retail and residential units ("rooftops"). Modern Planning holds to the pretense that these ratios are fixed and predictable, but history (even over a few years or a couple decades!) always shows that the ratios of retail (and office, etc.) to rooftops is quite dynamic. On the "supply" side, distribution models change, products fall out of fashion, mail-order and on-line shopping rises, etc. On the "demand" side, residential demographics shift, economies and household fortunes change, occupancy rises and falls. Yesterday's corner store is today's bagel shop, the next day's Ke-bab Palace, tavern, coffeehouse, social service agency, or something-not-yet-invented store.
What's important to "future-proof" a neighborhood is to:
- get the urbanism right, so that whatever the business, it "works" because of the logic of the place and its surroundings
- understand - and prepare for - those places in the urban fabric
that will tend to favor commerce (i.e. busier, well-located
intersections); which places will tend to favor residences (quieter,
non-through streets) and those places in between which may accommodate
both and/or the increase/decrease of one or the other through time.
These "in-between" or "transitional" zones are particularly important,
in my opinion, and an under-explored area in New Urbanism. (This
continuum is the genesis of the urban transect, an idea adapted from environmental studies. As an aside, I learned once that "transitional" plant species - those that grow at the edges of wetlands - not in full wetlands or full uplands -
are more drought-tolerant than either wetland OR upland species. The
reason is they are adapted to dramatic changes in hydration,
whereas upland- and wetland species are not. There is an analog here, to the "transitional" zones in neighborhoods, which may be residential one generation, commerce the next.)
- build commercial buildings that are either cheap/light enough to be disposed of or relocated when their site demands/supports more intense use; OR robust and generic/flexible enough to accommodate dramatic changes in use without major renovation. Each approach is inherently "sustainable" (resource-efficient) but may be called for in different conditions (some of which may be adjacent.)
- finally, employ "zoning" (or get rid of it altogether!) that permits easy changes in use, and let, instead, the urbanism (per #2 above) guide where/how different activities are decanted throughout the town. If the urban fabric is "right", the quiet, narrow, indirect street will never be attractive for the 7-11 (or whatever) and the busy corner will never make sense for a mansion. Perhaps this is the next frontier of urban design; "legible" urbanism that directs use through the inherent logic of its fabric.