I understand that they're trying to point out how refreshing water is,
and especially how thirst-quenching Dasani water is.

Yet, at around 9 to 10 bucks a gallon,
I don't think many people would be dumping this stuff over their heads.

Don't spill it, but feel free to dump it over your head.  

 Of note, though not really related to the Dumb-ness of this ad:

Soft Drink giant Pepsi noticed that bottled water was becoming popular, so they started marketing purified tap water under the name "Aquafina."
Coca-Cola responded by marketing their purified water product, "Dasani."
HOWEVER-- Dasani adds three types of salts to their water; Magnesium Sulfate, Potassium Chloride, and Sodium Chloride (table salt.)  Why do they add salt to their water?