Originally Posted by
Pluma
It is to prevent arriving passengers from having communications with a corrupt immigration official. I assume this was a method that incoming bad guys used to talk with the corrupt officer to find out what booth he was at, and then somehow go to that booth.
If that were the real reason, it would be much more effective to prohibit the officers from having cell phones in their booths and do 100% monitoring or recording of their wired phones and/or 2-way radios. It's much easier to root out one corrupt officer among a staff of a few dozen (or even hundred) than to root out one corrupt passenger among tens or hundreds of thousands.
It's a power trip. That's the real reason.