This isn't uniquely an Indian phenomenon. I have many esian friends, mostly from west of china, all the way to Saudi arabia who eat like that. I'm not going to lie, it doesn't bother me, because when I invite them for dinner, it's much easier to do the dishes! I found it a little weird how long one of my friends went without washing her hands after eating though. We were watching a movie, then about 2/3 the way through she finally washed them.