Help!!! - "The Auntie Protocol" - What is Right??

For all readers of my blog who hail from Western cultures, here is a little background - it is well know that when your brother or sister has a child, you will be know as auntie or uncle. You should also know that in many Asian cultures (and in many different languages), the term auntie and uncle are commonly used terms to address people of 'advancing' years (or perhaps those older than you), if you don't happen to know their name - regardless of whether or not there is any family relationship.

The purpose of this post today, is to solicit any information from local Singaporeans (or anyone else) on the appropriate protocols of when the term should or shouldn't be used.

The reason I ask, is when our friends' children call my wife and I auntie or uncle, we have absolutely no qualms or issues, and in fact we often feel a great deal of respect from these kids.

However, today when we were leaving Cold Storage shopping centre at Causeway Point, I was pushing the trolley full of purchases, and behind my wife was pushing Jaime in the pram. A few metres from the exit, I heard my wife raise her voice - because my hearing is bad at the best of times (and the noise around was quite overwhelming), I did not know what was being said or to whom, except for the loud use of the word "Auntie!!"

As I turned to see what was transpiring, I saw my wife with a very distressed look on her face, and beside her an 'auntie' of around - I'm guessing - mid-50s, also with a very unhappy look on her face.

Now I know that Sammi is usually very reserved and would not be raising her voice for no reason, and my first impression was that she was engaged in some sort of argument. By the time I walked the few steps back to the pram, the elderly lady had walked away, and Sammi was still talking to me in a 'very loud' voice. I could still hear her using the word 'Auntie'.

First impressions are often very wrong, and there was in fact no argument between my wife and this lady. As it turns out, she had approached Sammi to ask her for the stamps she had received with the receipt from Cold Storage (you know, the ones where if you collect enough you can exchange them for pots and pans, or baggage, or whatever the current promotion may be).

The lady, not knowing Sammi's name, called out to her - "Auntie, Auntie" - to get her attention. In Shanghai (my wife's home town), the term 'Auntie' is never used (as a rule) to address someone younger than you. So what I first took to be anger on my wife's part, was actually astonishment at being addressed in such a way by someone who could be almost twice her age. The raised voice was not at the lady, but at me to draw my attention to the situation - even later this evening, it was still on Sammi's mind - "how can someone that old call me Auntie - unbelievable!!!!"

So, my dear readers - what is the protocol?? - when is it acceptable for someone to address someone else as Auntie or Uncle?? Is it dependent on age? Is it prehaps dependent upon whether or not one has their own children? Or is it 'free for all'? ie. can the terms be used anytime that you don't know the other person's name? - I couldn't imagine calling a teenager 'Auntie' or 'Uncle'... nor do I have any problems calling the elderly guy who serves me drinks at Yong Heng hawker centre, 'Uncle'... so what is the right thing??