Originally Posted by JohnDThompson

The Hmong are indigenous to an area with year-round high heat and humidity. Drinking ambient temperature water keeps them well hydrated without a need for cold fluids.

You may have a preference for cold fluids, but that's all it is. Adequate hydration is far more important than the temperature of what you drink, and my preference is to carry sufficient fluids and not worry about the temperature of said fluids.