Why do studios use Roman numerals in the copyright notice in the end credits?

© Time Warner Studios MCMXCVIII

Something like this is almost always used at the very end of the credits creep in movies (and TV shows). But why the cumbersome use of Roman numerals? Why not just say 1998 and be done with it?
http://movies.stackexchange.com/ques...he-end-credits


I love some of the answers on that forum that people gave The thing is I've seen Roman Numerals in far more places than solely ending credits on a movie. So how can they explain that then? IMO the "UNITED STATES" & other "STATES" are under control of the Vatican to this day. Nothing else makes much sense when you closely examine the facts.