A big 'problem' here in the US is that many communities both chlorinate and fluoridate the water - the chlorine has both an obvious taste and odor, neither of which is pleasant, and many people don't care to be imbibing 'large' quantities of fluoride. There are also communities where lead is a problem, due to an ancient plumbing infrastructure (parts of Boston, Washington DC, Richmond VA, etc).
As for me, there's nothing that compares to natural well water - yes, we carbon filter it, due to possible organic matter, but otherwise, it's just water, and nothing more.