For starters tho
So large fast societies can't feel grief? Thinking people cant feel?(that must be wrong!)
Two words: Princess Diana.
I don't think it is that large, fast societies cannot feel grief... but being in such a society makes it all-too-easy to avoid grief. People are constantly distracting themselves as much as possible, and at times I've known individuals well enough to know that their near-desperation for distraction is because they don't want to feel the emotions that would surface if they were not distracted.
It is unhealthy to avoid grief and it traps us into cycles... and from living in the city that I live in, where distraction seeking and grief avoidance are high, I see a lot of people who are stuck in cycles, don't understand how to escape them and frankly they often show no desire to escape them either.
So I don't think that people become incapable of emoting, I think that as more distraction is available they avoid the emotions and can ultimately get to the point where their life is nothing but a series of distractions and a lack of any real emotional attachment.
But as always, it's not across the board and while a large portion of a society may behave in this manner there are always exceptions.
I may be disagreeing with points Sushil has made... I'm not sure as I only skimmed the many lengthy posts. I definitely agree with what I picked up though.