A rule is only lawful if it complies with the bill of rights. This obvious violation of the first amendment is simply not lawful.
Furthermore, when we make a go-no / go, cookie-cutter world and abandon our ability to exercise discretion in our decision making process, we put the machine ahead of its operators. This is one of the best reasons there is to refrain from making a plethora of SILLY rules for every type of behavior. Winston Churchill said it best:
"If you have ten thousand regulations you destroy all respect for the law."