They are from a feared and highly known clan that produces arch-wizards that are feared - the comments made in the anime are as if telling a legend or myth about this group who can eliminate towns and their name is something childish like what two close young friends would use to call each other.
Imagine if trumpets were blaring and messenger boys would ride upon horses, rolling out a red carpet then throwing rose petals, opening a proclamation made from a rolled scroll and announcing that SillyBilly has arrived.
