The You Own The Data Act Yoda Was Introduced On (old.reddit.com)
When you accept the package, you become a verified buyer automatically, and the scammer can use your verified buyer status to create fake reports for products on websites. Ie they created a buyer account and put your address, and after receiving a package at your/their address they can review products.
If you receive one, it means likely your data is compromised, so do another check.
The scammer knows the name on the address is legit, so they may use it more.
Sometimes the envelopes/packages are empty, sometimes they have little objects in them like baseballs.