Surprise! Many bottled waters also contain chlorine or chloramine (a chlorine relative) to keep them fresh. The levels are usually lower than tap water, but don’t assume it’s a chlorine-free oasis. It’s just better at hiding its personality.
And if you really dislike the taste, a simple carbon filter pitcher (like Brita or Pur) removes most of the chlorine. Boom—you’ve upgraded from “poolside” to “spring morning.” You’re welcome.