Vital point striking is, basically, a "sniper analogy":
Aim small, miss small
Aim big, miss big.
In layman terms:
Aim for the head, miss the head.
Aim for the side of the head, hit the head
Aim for the jaw, hit the side of the head.
Aim for a spot on the jaw, hit the jaw.
All striking arts aim for vital points, the thing is that you want to aim and hit the ones that work all the time and on everyone and those are the typical ones that everyone knows.
Sure there are some nice ones that work really well as "coup de grace" by why use them when you don't need them?
As for pain compliant ones, well...you are putting your trust on something that you don't know and that is the pain threshold of your opponent, not a wise move IMO.
Psalms 144:1
Praise be my Lord my Rock,
He trains my hands for war, my fingers for battle !