"Tap" doesn't always have a uniform flavor, even in the same city. It's perfectly possible that bottled tap might taste better than the tap water at your house.

I was just in the US and I couldn't drink the bottled water, basically, due to it tasting terrible. The San Francisco tap water was surprisingly good when filtered, and I did find a brand called "Iceland Spring" or something similar that was good. Evian also has a consistently good taste.

yes a lot use tap water but they almost all invariable will go through a RO system and ozination and/or uv with some minerals added back in at the end for taste. the RO water with minerals tastes better to me than a natural spring water without that treatment. (used to work in water purification for a spell)