(Emphasis mine) Indeed it is a hard line to draw. One might argue that people partaking in extreme sports bring it on themselves when they have accidents or people who eat poorly because they can't afford good food might get caught in the system. If an insurance based universal system was implemented this could be tailored to the patient's needs/behaviours.
Personally I wouldn't advocate this however I like it how it is now in the UK where self-inflicted puts you at a low priority and bans you from certain procedures unless you change e.g. liver transplants for alcoholics.