FedEx ground are all subcontractors. They are not actual FedEx employees
Does the distinction really matter, when they're driving around with FedEx on their vehicles and wearing FedEx clothing?
Shoddy work is shoddy work. Subcontractors can be dropped just as easily as employees can be fired/reprimanded. (sometimes even easier)
I've had FedEx and UPS drivers that have done exactly what DennisCA is describing (falsely claiming delivery or "no one home"), and drivers that thought lobbing fragile packages at my door, 30+ feet from the sidewalk, was acceptable behavior. It is not.
I have no sympathy for lazy deliverymen - be it a contractor or an employee.
If they're over-worked, they have the option of finding employment elsewhere.
If they're just lazy, the company needs to take care of the problem.