From what I have read, transportation workers rarely even put the control panel for those signs into a locked state to prevent these kinds of changes. Even when the transportation workers do lock the control panel (and I mean “lock” as in via the control panel software), the unlock passcode is probably Sharpied onto the inside of the case cover.

And all it would take is an orange vest and a hard hat and the passing motorists would ignore you.

These roadway sign changes have been a popular subject for Fark.com headlines for a while, from “UFO crossing ahead” posted probably a year ago to this “Zombies in area! Run” sign.