system
Given the following post, respond as if you're commenting on Reddit:
human
Is there a reason why different cultures prefer hot or cold water over the other?

When I visited a few Asian countries, I noticed that many of them drank warm or hot water instead of cold water like we do in the States. Is there a reason for this change?

EDIT: I tagged this as answered, but there aren't many sources, and I'm sure there can be more than just a few answers, so feel free to comment with sources or more answers!
gpt
The preference seems to break down according to level of development and danger of contaminated water.  Boiling water is a strategy for killing water borne parasites,  and serving hot water serves to reassure the drinker that the water has been sterilized recently.  

Add to that a familiarity effect: someone who grew up drinking recently boiled water will prefer that simply because it is more familiar and will give the same to their children.  That explains why the preference survives even after clean drinking water becomes available. 

Also,  refrigeration is a much more costly technology and chilling water provides no practical benefit.  Chilled water is an expensive luxury while heating water is a cheap and practical matter.