I too felt guilty about my desperate purchase of Dasani on Friday, but perhaps for other reasons...

Water, Water Everywhere, but Guilt by the Bottleful

On a recent family vacation in Cape Cod, Jenny Pollack, 40, a novelist and public relations associate from Brooklyn, did something she knew she would come to regret. She did it on the spur of the moment. She did it because she felt desperate.

Besides, the giant illuminated Dasani vending machine was just standing there, like a beacon.

So, with her reusable plastic Nalgene bottles dry and her son Charlie working up a thirst in an indoor playground, she broke down and bought a bottle of water. To most people it would be a simple act of self-refreshment, but to Ms. Pollack it was also a minor offense against the planet — think of all the oil used to package, transport and refrigerate that water.

“Something about it felt like a betrayal,” said Ms. Pollack...