Common misconception due to movie brain. The average "salary" of a misc gang member is under <30k per year. Violence is cheap any male under 30yo can easily do it and the poor ones are often willing. Junkies will often do anything including murder for next to nothing ie another hit. Junkies are actually quite reliable contrary to movie brain beliefs.
Anyway wrench hitting does not need to scale. They only want the passwords of people they perceive as being a threat to them which is a very small number of people.