So I can give a real life example of the type of customer that uses these exclusively. My previous employment was leading development on a media scanning statio

So I can give a real life example of the type of customer that uses these exclusively. My previous employment was leading development on a media scanning station, a bit like an ATM, but with a lot of ports in front to accept USBs, CDROM, etc. We provided this product to the energy, defense, pharmaceutical, etc sectors. Essentially critical infrastructure. Many of our customers utilize air-gaps to isolate their critical systems. So to get files into those systems you basically have to sneaker net it, usually using portable media of some kind. The basic procedure using our product was to take an "unknown" piece of media with the files you wanna move over. Slot it into our station, then grab a "known" piece of media and put it into the other port on the station. The station would scan all of the files using several commercial AVs, then files deemed to be clean would be copied to the "known" piece of media. The important thing about the "known" piece of media is that its generally one of these expensive USBs with FIPS encryption, and crucially the FIPS epoxy and digitally signed firmware on the controller. Often these facilities are like onions with several layers of security, and this procedure must be done several times to get to the truly sensitive equipment, along with guards checking receipts and unlocking media from lockboxes, etc. Having everyone at the facility using the same drive, especially if you can purchase in known serial numbers, is good practice. That way anyone using a different model drive is easily spotted and programmatically you can lockdown to those known serials before mounting. Similarly if someone tries to take it apart the FIPS epoxy should destroy the internals of the microcontroller. They drill through the epoxy and flash the firmware, the microcontroller in these drives will reject cause it is not signed. Finally, if they do manage to build an exact replica, with the correct serials but some nasty internals, it wont matter since they are forced to use a "known" drive before stepping up to the next security level (the bad drives gets left at the low security gap). Its not perfect, but it does build defense in depth, especially with more mundane things added into the mix like FBI background checks, etc. You quickly get into mission impossible scenarios requiring physical agents gaining access to reach the inner layers of these critical systems.