It strikes me as crazy for an appropriate value of the word. But I grant that it doesn't work for some values of the word.

Re: the analogy, I see the analogy as closer to "if someone jumps into your lifeboat, and puts your life in danger thereby, and you want to kick them out", which is a far cry from murder to enable cannibalism.

But I grant you, I know some people, who generally seem reasonable, would make the argument you gave.