Roman Numerals

I can understand the confusion about some of the Roman Numeral rules. Especially the one about the "X" and not using more than 3. However, I received 2! related publications in the post today that makes me think that Roman Numerals should be taught in math classes in primary and secondary schools once again. What, exactly, is the point of putting "XLX"? The volume number should be 50 and that's what this one winds up being -- but how obtuse can you get?!