You were literally not raised to say "Hello" if someone said "Hello" to you in a store, on the street, or in a public location? There's also a thing we call "the Cali nod" which is you acknowledge the presence of another - it's not intrusive, and as a matter of fact - how can you think saying "Hello" is rude? The pool is a public location (within our community)/. Well, I am sorry to hear that and actually, there WAS something wrong with these people and I hope and trust you misunderstand what I wrote and you were merely from a very restricted background that did not expose you to ... the way the majority of people interact.