I think moustache bars are too old for our time frame. At least in France, they were superseded by the "3 position" bars, which we now call drop bars. I read somewhere that cyclotourists started using the "3 position" because they offered more hand positions, and that racers later followed suit. Must have been in the 1920s or earlier...
All the classic French touring bikes (1930s onwards) were equipped with either "drop" bars (became popular after WW II), randonneur bars (rarely after 1960), or (for less performance-oriented riders) swept-back bars.
Jan Heine, Seattle (who likes randonneur bars a lot and moustache bars not)
P.S.: This isn't to say that moustache bars are bad, or shouldn't be used on a classic bike, etc. etc.