I think Ethos water is a ridiculous scam. I say this, by the way, while being a relatively loyal Starbucks customer (probably 5x a week) - but I just can't help but get really peeved.
Take a look at this article from TrendHunter.com: http://www.trendhunter.com/trends/charity-profiteering-the-ethos-water-scam. Jeremy Gutsche does a great job exposing this fraud. 5 cents a bottle as a donation when the bottle costs $4? Pass. Get bent, Ethos. I'm buying a $1 bottle (or drinking from the fountain) and donating to a real charity.