So the main reason that they don't have self-serve kiosks is security.
Security
THEATER. How does handing a sealed box to a clerk who just tosses into the bin any different than me personally placing it in a drop box? (Answer: none f'ing at all)
UPS has taken security a step further by requiring ID when you send a package.
Since when? I've shipped dozens of packages and never been asked by any clerk or driver for any form of ID at all -- hell, they don't even ask for ID to
deliver packages. And BOTH UPS and Fedex have drop boxes all over the place.
(ironically, the one time (over 20 years ago) I've had to show ID and sign for a package was with, wait for it, USPS. There's a *reason* law firms use private couriers these days... ups/fedex/usps don't honor their "hand-deliver, id required" options.)