Great idea Zanthrus but...you may well get a letter back threatening you with prosecution for .."using a carriage service with an obscene, threatening and offensive message"
They can dish it out but make any push back comments about their perfidy and idiocy...they really hate that. But they have plenty of time and money to waste on threats that may or may not be so idle.
We sure have entered well into the age of Bureaucratic Stalinism.