Well, they are free to do so.
There are only so many times I can type  in a thread before it stops being funny. However, it is totally funny the first few times.
Miss Chicken wrote:
The foundation stone for the Penitentiary Chapel in Hobart says Anno Domini M.DCCCXXXI (1831) and the Chapel's clock has Roman numerals and was built in 1828 by Thwaites and Reed of Clerkenwell, London (it was one of 4 clocks in a single order that authorities in Tasmania bought from Thwaites and Reed).
Any appearance of Roman numerals before 1934 is the result of time travel.