The thread that refused to die!:) if you live in south-east Asia for a while you notice some commonality among the languages, and one is the lack of words ending in s. Laos with the s sounds odd, Lao without the s sounds far more natural. I think I'm right in saying that in Chinese (my wife's Singaporean Chinese) there are no words ending in s either, at least in the main dialects.
Anyway, that's my final word on the matter!