Forum Moderators: buckworks
The two are used in tandem during purchase as a fraud measure- it's easy to see rough distance between a billing address and billing phone number. There are legitimate reasons why they may differ, but it's a useful flag.
We use the zip code database for geographic reporting: how many orders come from local customers, distant customers; geographic distribution and other reports meaningful for our kind of widgets.
There are a lot of vendors offering the same data. One in particular is inexpensive and has good distribution and attention to detail. I won't name them, so let's just say they have a world of zip code and area code data.
Our UPS shipping computer will detect mismatched cities/zips, I believe.
We sell to many businesses which are often located in areas with low home values and average income. Separate ship/bills are common in our business and aren't significant indications of fraud.
In the rare case where we really want to research an order for fraud, the 20 free look ups might be useful and far more than we'd ever need. I've bookmarked that page.