Not in my area (San Francisco) but I do it anyway especially to my 'true' elders. I think it shows respect. I do hear it alot at my church though. A good portion of my church members are from the south or their families are from the south so it's not uncommon to hear a ma'me' or sir. Sometimes as I'm passing the hotels downtown, I hear the porters/bellhops using the term.
When I was attending Grambling, a little boy[about 8 or 9] called me ma'me [I was 21 at the time] and it freaked me out for 2 reasons.
The first because I thought I was too young to be call that.
The second because I was actually pleased that he gave me that respect as his elder.
