[usrusr]

If you want a rationalization for that idiom, think of a state machine: they are in a state of need, therefore they kill. Note also how acting "out of" does not necessarily imply transitioning away, e.g. company x operating out of city y.

The grammatical nuance between out of need and out of luck (nice find btw) would be doing (out of need) vs being (out of luck): you might win out of luck, and later lose because you are out of luck. Wastefully spend out of wealth, then be out of wealth, and so on.