Most BigCos have two fundamental rules: you can't use any non-approved software[0] and you're to be at your desk at all times, even when you have no work to do. Given those restrictions, this makes perfect sense (although, a stealth switch works better[1]).
Believe it or not, most companies outside of tech are very controlling of what their employees can and cannot do with their computers. As an example, my first job out of college was with a NY branch of a multinational swedish-owned corporation that made airplane engines. One day, a top ranking employee walked out of the office with all of their blueprints on a usb drive and gave it to their biggest competitor[2]. Ever since then, they've forbidden any kind of physical data transfer, going so far as to pull all the cd and dvd burners from all desktops and disabling the USB drives (as much as possible).
anyone frustrated with the policies of their workplace is to invest their time on finding a better workplace
That's not an option for some. Not everybody works as a programmer. Aeronautical engineers, for example, have a limited number of employers. If you're not willing to relocate away from friends and family or you're not built for the city life, same thing.
[0]: Some even do network scans to check for unauthorized software programs on your hard drive [1]: http://stealthswitch.com/ [2]: Yes, it's illegal, but I imagine he was paid enough ttraino risk it and even if he wasn't, it doesn't matter: once the blueprints are compromised, they can never be uncompromised.