Whatever the security justification, locked-down computers often cause angst for workers and lead to attempts to work around the blocks. However, I can't see any reason why machines designed for public use, such as shopping centre kiosks, shouldn't be effectively locked down to avoid embarrassing scenarios like the one pictured.
The image, from the Australian Newsagency Blog, shows a shopping centre directory display in an advanced state of derp. Unlike the author of the original post, I don't agree that this proves a manual system would be better; in gigantic shopping centres, printed maps are often too small to readable, and they're not easy to update. What it demonstrates is that embedded systems need to be set up so that in the event of a crash or a long period of system slowness, they reboot (and perhaps restore) automatically.
When a manual system works better than a computer [Australian Newsagency Blog]