Quote Originally Posted by Iscah View Post
The one oddity with assuming "Chai" is a family name is that people address Chai-Nuzz as "Master Chai" and that phrasing usually uses the person's given name... but then again we've never dealt with any races that don't put their given name first.
Self-correction here... was rewatching the Crystal Tower cutscenes, and Rammbroes addresses Cid as "Master Garlond".

It may be more about how few characters actually have surnames, or at least commonly stated ones.