> It depends on where you are in the world, but in most places in the civilized world, criminal law does not work that way.
I'm sorry, but: no. "In most places in the civilised world" there are these guys called hairdressers and they could routinely - technically - be charged with committing assault causing bodily harm. It's a pretty clear cut (sorry) case that gets trotted out in most any first year criminal law class. The reason they aren't charged is simple: you consent to that bodily harm being inflicted upon you. There are variously defined limits to your ability to consent, especially with regard to duress or excessive harm, but your reasoning is otherwise completely incorrect.
I'm sorry, but: no. "In most places in the civilised world" there are these guys called hairdressers and they could routinely - technically - be charged with committing assault causing bodily harm. It's a pretty clear cut (sorry) case that gets trotted out in most any first year criminal law class. The reason they aren't charged is simple: you consent to that bodily harm being inflicted upon you. There are variously defined limits to your ability to consent, especially with regard to duress or excessive harm, but your reasoning is otherwise completely incorrect.