I say "hi" whenever I pass any of my neighbors. Most of them look at me like I'm crazy, and usually don't respond.
I am always to polite, no matter where I am. I continue to say "Good morning!" and the response is always, "Buenas dias!"
I actually got an entire sentence out two months ago...I was reprimanded for saying "Good morning" and when the woman insisted I say "Buenas dias."
In my limited Spanish, I said, "NO! This is the US! You learn American! In Mexico, I speak Mexican!. No habla Espanol!"
She hasn't spoken to me since.
Maybe you really ARE crazy and don't know it! :P