To the extent that there's no state, other measures must already be in place, under ancap logic.
That's why it's "anarchocapitalism," and not just "anarchy."
Your argument is like saying, if people opt out of government healthcare, they can't come crawling to the government when they're sick....But people are opting out based on the understanding that the market can provide infinitely cheaper, more effective, and more efficient healthcare.
The ancap argument has two components. One is the moral, anti-mafia position, and the other is the understanding there's a preferable method of organization waiting to be utilized.
With a functioning market, a solution, or the prevention, of every situation you describe, would be available to the victim before the incident occurred. If someone chose to not have insurance or not to take preventative steps of some kind, it's not the responsibility of the rest of us to pay for their stupidity. However, with a functioning market, the abundance produced would likely provide charity or some means to clean up messes made by idiots....it would be in everyone's interest to not have cars sitting wrapped around trees, or robbery victims bleeding out on the corner.
Your simplistic hypotheticals don't take into account the many levels on which the market functions, and the endless forms market solutions can take.
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