Staying creates the obligation. You may not understand the value of having been born in a stable nation, but that doesn't mean you didn't benefit from it.
Staying isn't an action or a means of positive assent to some kind of obligation to be imposed on others.
I guess if a woman stays in a neighborhood she consents to being raped?
In the case of taxation it is. It isn't nearly staying, or leaving. It is a matter of receiving the benefits everyone there pays into, while acting as if you dont have to contribute.
