The maam sir thing is a little annoying to me. It's not that I have less respect for someone, it's just that I don't feel the need to distinguish. I think manners can be summed up not to proper phrases and gestures, but to being a genuinely good human being.
i dunno. in the south it is generally accepted/ even expected at times. i've noticed some millennials get offended when you say it. awesome. making people uncomfortable with kindness is so much fun.