> All that means is that as the receiving party there is absolutely no reason for me to sign anything, or even use my actual signature.

Yes, but this actually doesn’t matter.

The only time when the signature on file is actually relevant is when the sender lodges a claim for non-delivery. In that case, it could be compared to your actual signature.

Conversely, if no claim is lodged, the package must have been successfully delivered.

Disclaimer: not a lawyer.