How does FedEx know what's in my package? Are they opening all the packages?

From Fedex Package
Return-Path: <info@fedex.com>
Received: from 41.203.64.132, Lagos, Nigeria, Ilesa Glo-mobile Network Services
Received: from 41.203.64.132 ([41.203.64.132]) by webmail.ctlconnect.co.uk (IMP) with HTTP for <s.richmond@ctlconnect.co.uk@localhost>;
Date: Fri, 29 Jun 2012
From: Fedex Package <info@fedex.com>
Reply-to: [fedexdeliverys2@yahoo.com.hk]
Subject: Good Day!!!

Good Day!!!

We have a package for you,This package contain a check of 5Million United State Dollars ($5,000,000.00USD),It shall be deliver to you as soon as we hear from you via Email.Contact me via Email for more information.My Working Email address is : (fedexdeliverys2@yahoo.com.hk)

Best of Regards,
Mr. Anthony Bright