That's a really interesting observation and substantiates a suspicion I've had: people generally have a good idea in mind of what they're going to buy and about when they're going to buy it. If at a particular moment the opportunity doesn't present itself, they'll simply delay the purchase until it's possible.

This would apply more to purchases from a specific and exceptional point than those which can be made from multiple providers. Say, my usual lunch spot is closed or out of an item, and I can walk down the street elsewhere (or a drugstore, etc.). However if you're selling hard-to-find exclusive items, or we've got an established relationship and the item isn't something I need right now, I'll simply get it later.

On the macro scale, it makes me suspect that shorter interruptions to service don't have a significant regional financial impact.

Though this is all armchair economics.