Simply put, its just too easy to get caught clipping someone with todays technology.. Cell phone records,camera's, dna, and of course witness '.
Murder is much more of a last resort these days.
Back in the. 70's and 80's there was always an article in the new york post about a guy shot in the back of the head or a guy found dead in a trunk.
Cell phone records can also pin point where you were at a given time.