Perhaps not in quite the same vein but equally stupid, I own a 1971 tractor and, apart from when I bought it, I have always taxed it online. That being real easy as no MOT required, only insurance and its also free, due to age I suppose. For the first couple of years the tax disc came back as AG MCHNE (Machine) and no more was heard. This year I did the same and it came back as before AG MCHNE. About a month later I received a letter stating ...... Our record shows there is a difference between the information sent to us by the issuing Post Office and that on the tax disc for your vehicle.
As Homer would say DOH
The upshot of all this is that they sent me a replacement tax disc and its now classed as an HISTORIC. I had to return the offending tax disc!