This is true of FedEx, but not UPS. At FedEx, you have the FedEx Express and FedEx Ground divisions, where the ground subsidiary includes the FedEx Home Delivery operation. A driver for FedEx Express won't drop off a FedEx Ground package, and vice-versa.
Originally Posted by kevinpy
At UPS - everything is integrated. One company handles all Ground, Air, and International shipments, and one driver delivers all those shipments on their regular route. So instead of having 3 drivers deliver packages in one area (Express, Ground, and Home Delivery for FedEx), UPS only has one driver in each area delivering packages, which helps cut down on costs.
This integration also allows UPS to save on transportation costs. Example: You send a package 2nd Day Air from Minneapolis to Chicago. Instead of flying that package down to Chicago, UPS will put it on the next truck down, saving costs, while still meeting the delivery guarantee of 2 business days.