[LaGrange]

In fact I tried San Francisco water, and it was completely fine. And there's also the obvious question about the carbon footprint of bringing coconut shells to US for manufacturing.

On the other hand, in several places in Poland a water filter is, actually, fairly useful.

[chockablock]

I use a carbon block filter (Clear2o) for SF tap water, and appreciate the lack of chlorine taste. (Or more properly, chloramine: http://www.sfwater.org/index.aspx?page=357 )