A lot of Indian co's in High street etc., are actually founded by and mostly staff by two main racial / language groups - Punjabi and Sindi. These Sindis are actually from Pakistan but migrated to India/oversea during partition of India. Punjabi in SG are mostly Sikh but you will find Hindu Punjabi with exact same family name (such as Bajaj) minus the beard. To add to the confusion, some Sikh do shave beard, so just by family name or looks it is hard to tell.
There is no northern monopoly on ligher skin as you will find contrary examples everywhere. That is why Churchill said of India - whatever you say of them, the opposite is also true..
Using lanugage not understood by some in a gathering, in a deliberate manner, is rude and shows bad upbringing. Unfortunately many do it, without realising how rude it is.