Role of small talk in academia Small talk in the title refer to the small questions or words that are culturally used in preserving and maintaining relations among people.
The normal small talk are as follows

How are you?

How is your health?

Happy married life.

I am deeply saddened by the news of your brother passing.... etc.,


Actually, all these are more relevant in case of relatives, extended family and personal relations. But, I observed that lots of people in academia network also does the same.
Is there any purpose in small talk? Is not engaging in small talk an improper etiquette?

Consider the situation in which a lab mate underwent a life event and everyone in the lab is wishing or showing condolence for the same. Is it improper to not care about it as it is an personal level or non-academic achievement?
People who work together find it natural to also interact in small (or large) ways not connected to the work itself. We aren't robots programmed to do a job and the job only.
Over time, a certain level of caring might naturally develop among colleagues, even when their primary communication is about work.
And, I'll guess (and predict) that this level of  human contact actually makes the work easier and more efficient when not taken to extremes (three hour poker or D&amp;D sessions, say). I think many of us have the experience that it is harder to work with someone who refuses to do this and sets up a wall of isolation. Integrating a new person into a work environment often takes a fair amount of this sort of interaction.
Life is life. Work is only a part of that. You don't put your human nature in a box when you go to work, I hope.