alt Hacker NewsExcellent question it certainly does come up. Practically speaking the more populous zip codes are all accounted for and that’s where the vast majority of deliveries go to. For example I took the census zip code data 150 miles (crow flies) outside Philly and found virtually 100% coverage.
For missing ones you have to fall back to distance based estimates and in my business that means you’re quote may be off and you’re exposed
No shade whatsoever at you or your business: I'll say upfront that you certainly made the right practical decision for the goal of running a business.
That said, this is a textbook example of what I have always found so infuriating, personally, about working on commercial software, and one of the many reasons I ultimately moved into a non-software-writing role. The (very sensible and practical) shortcuts and tradeoffs that are commonly made due to time and cost constraints. The attitude of "well the vast majority of our use cases work, so we're done." I've always thought edge cases must be addressed. Something in my brain hurts when I knowingly release something where only 99% of cases work.
I can imagine this is probably the same thing some artists feel when they are commissioned to produce (in their view rushed, flawed, or incomplete) artwork for business purposes.
I only write software at home, as a hobby now, and this gives me the outlet to follow my heart around edge cases!