Most games won't do that as it just impacts the fun of it if you accidentally off some 'innocent' NPC and now apparently the entire world is out for you, after finding out somehow. Perhaps it's also skipped as it may be tedious to implement and ensure it's not some massive bug waiting to happen. I think that most games I've played that allow you to kill people do have some sort of response set in - reputation loss or guards or bounty hunters.
The idea of GTA having police want you forever because you killed some hooker is a bit amusing, goes against the spirit of that game But even so, no one is making you kill people for no reason or even incentivizing it. Certainly is possible, though tricky to complete the game in a 'clean' manner where you don't ice a tonne of innocent people.
That entire episode was pretty weak, though I will re-read it, background NPCs are background NPCs and have no depth. Surprise!