Sorry, could you go into more detail here? This happened to my mom several years ago, and we always wondered why.
Buy item from using junk email address and shipping address of person B.
On delivery day, wait near person B's home, and grab the package when UPS delivers it. If person B manages to get to the package first, scammer is only out some time.
Junk email and 3rd party mailing address - harder to track scammer. Of course, this ignores IP address and similar - smart scammer would also use Tor and other tools to obfuscate the online transactions.
Creating fake orders to enable fake reviews for a product to be posted, boosting the product listing.